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MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
MOC's Highest Resolution Vie
PIA02352
Sol (our sun)
Mars Orbiter Camera
Title |
MOC's Highest Resolution View of Mars Pathfinder Landing Site |
Original Caption Released with Image |
Can Mars Global Surveyor's 1.5 meter (5 ft) per pixel camera be used to find any evidence as to the fate of the Mars Polar Lander that was lost on December 3, 1999? One way to find out is to look for one of the other Mars landers and determine what, if anything, can be seen. There have been three successful Mars lander missions: Viking 1 (July 1976), Viking 2(September 1976), and Mars Pathfinder (July 1997). Of these, the location of Mars Pathfinder is known the best because there are several distinct landmarks visible in the lander's images that help in locating the spacecraft. The MGS MOC Operations Team at Malin Space Science Systems has been tasked since mid-December 1999 with looking for the lost Polar Lander. Part of this effort has been to test the capabilities of MOC by taking a picture of the landing site of Mars Pathfinder. An attempt to photograph the Pathfinder site was made once before, in April 1998, by turning the entire MGS spacecraft so that the camera could point at the known location of the Mars Pathfinder lander. Turning the MGS spacecraft like this is not a normal operation--it takes considerable planning, and disrupts the on-going, normal acquisition of science data. It took 3 attempts to succeed, but on April 22, 1998, MOC acquired the picture seen on the left side of Figure A, above. The three near-by major landmarks that were visible to the Pathfinder's cameras are labeled here (North Peak, Big Crater, Twin Peaks). It was known at the time that this image was not adequate to see the Pathfinder lander because the camera was not in focus and had a resolution of only 3.3 meters (11 ft) per pixel. In this and all other images shown here, north is up. All views of the 1998 MOC image are illuminated from the lower right, all views of the 2000 MOC image are illuminated from the lower left. As part of the Polar Lander search effort, the Mars Pathfinder site was targeted again in December 1999 and January 2000. Like the 1998 attempt, the spacecraft had to be pointed off of its normal, nadir (straight-down) view. Like history repeating itself, it once again took 3 tries before the Pathfinder landing site was hit. The picture on the right side of Figure A, above, shows the new image that was acquired on January 16, 2000. The white box indicates the location shown in Figure B (above, right). The 1000 m scale bar equals 0.62 miles. Figure B (above) shows a subsection of both the 1998 image (top, labeled SPO-1-25603) and the 2000 image (bottom, labeled m11-2414) projected at a scale of 3 meters (10 ft) per pixel. At this scale, the differences in camera focus and sunlight illumination angle are apparent, with the January 2000 image being both in focus and having better lighting conditions. In addition, the MGS spacecraft took the 2000 image from a lower altitude than in 1998, thus the image has better spatial resolution overall. The 500 m scale bar is equal to about 547 yards. The white box shows the location of images in Figure C,, below. The third figure (C, above) again shows portions of the April 1998 image (C, left) and January 2000 image (C, right), only this time they have been enlarged to a resolution of 0.75 meters (2.5 ft) per pixel. The intrinsic resolution of the January 2000 image is 1.5 meters (5 ft), so this is a 200% expanded view of the actual M11-02414 image. The circular features in this and the previous images are impact craters in various states of erosion. Some boulders (dark dots) can be seen near the crater in the lower left corner. The texture that runs diagonally across the scene from upper left toward lower right consists of ridges created by the giant floods that washed through the Pathfinder site from Ares and/or Tiu Vallis many hundreds of millions of years ago. These ridges and the troughs between them were also seen by the Pathfinder lander, their crests often covered with boulders and cobbles (which cannot be seen at the resolution of the MOC image). The 100 m scale bar is equal to 109 yards(which can be compared with a 100 yard U.S. football field). The Mars Pathfinder landing site is located near the center of this view. The fourth picture, Figure D (above), shows a feature that was initially thought to be the Mars Pathfinder lander by MOC investigators. This and the following figures point out just how difficult it is to find a lander on the martian surface using the MGS MOC. Figure D was prepared early in the week following receipt of the new MOC image on January 17, 2000, and for several days it was believed that the lander had been found. As the subsequent two figures will show (E, and F, below), this location appears to be in error. How the features were misidentified is discussed below. Both Figure D and Figure F, showing possible locations of the Pathfinder lander in the MOC image, are enlarged by a factor of three over the intrinsic resolution of that image (that is, to a scale of 0.5 meters or about 1 ft, 7 inch per pixel). The right picture in Figure D shows sight-lines to the large horizon features--Big Crater, Twin Peaks, and North Peak--that were derived by the MOC team by looking at the images taken by the lander in 1997. After placing these lines on the overall image, there appeared to be two features close to the intersection of the sight-lines. Based upon the consistency of the size and shape of the lander as illuminated by sunlight in this image, the northern of the two candidate features (the small "hump" at the center of both left and right pictures) was considered, at the time, to be the most likely. HOWEVER... Later in the week following acquisition of the January 16, 2000, image (and over the following weekend), there was time for additional analysis to determine whether the rounded hump identified earlier in the week (Figure D, above) was, in fact, the Mars Pathfinder lander. A computer program that estimates relative topography in a MOC image from knowledge of the illumination (called "shape-from-shading" or, photoclinometry) was run to determine which parts of the landing site image are depressions, which are hills, and which are flat surfaces. The picture at the left in Figure E (above) shows the photoclinometry results for the area around the Pathfinder lander. The picture at the center of Figure E shows the same photoclinometry results overlain by an inset of a topographic map of the Pathfinder landing site derived by the U.S. Geological Survey Astrogeology Branch (Flagstaff, Arizona) from photogrammetry (parallax measurements) using images from Pathfinder's own stereo camera. By matching the features seen by MOC with those seen by the Pathfinder (the large arrows are examples of the matching), the location of the lander was refined and is now indicated in the picture on the right side of Figure E. The large, rounded hump previously identified as Pathfinder in Figure D (above), is more likely a large boulder that was seen in Pathfinder's images and named "Couch" by the Pathfinder science team in 1997. Figure F is summary of the results of this effort to find Mars Pathfinder: it shows that while the landing site of Mars Pathfinder can be identified, the lander itself cannot be seen. It is too small to be resolved in an image where each pixel acquired by the MOC covers a square of 1.5 meters (5 feet) to a side, given the contrast conditions on Mars and the MOC's ability to discriminate contrast. At this scale, Pathfinder is not much larger than two pixels, and the same is true of the lost Polar Lander. No evidence has been found in the January 2000 MOC image of the aft portion of Mars Pathfinder's aeroshell or its parachute, either. If the aeroshell is laying on its side, as interpreted from Mars Pathfinder's images, then it would be very difficult to see this from orbit. Because Pathfinder did not image the parachute, it is not known how it may be configured on the surface--it could be wrapped around the aeroshell or a boulder, for example. This effort to photograph the Mars Pathfinder lander demonstrates that it is extremely difficult to find a lander on the surface of Mars using the Mars Orbiter Camera aboard the MGS spacecraft. This analysis suggests that it is not very likely that the December 1999 Polar Lander will be found by MOC. |
|
Acidalia and Chryse Plains,
PIA02000
Sol (our sun)
Mars Orbiter Camera
Title |
Acidalia and Chryse Plains, Mars |
Original Caption Released with Image |
Somewhere down there sits the Mars Pathfinder lander and Sojourner rover. This Mars Global Surveyor Mars Orbiter Camera view of the red planet shows the region that includes Ares Vallis and the Chryse Plains upon which both Mars Pathfinder and the Viking 1 landed in 1997 and 1976, respectively. Acidalia Planitia is the dark surface that dominates the center left. The Pathfinder site is immediately south of Acidalia, just left of center in this view. Also shown--the north polar cap is at the top, and Arabia Terra and Sinus Meridiani are to the right. The bluish-white features are clouds. This is a color composite of 9 red and 9 blue image strips taken by the Mars Global Surveyor Mars Orbiter Camera on 9 successive orbits from pole-to-pole during the calibration phase of the mission in March 1999. The color is computer-enhanced and is not shown as it would actually appear to the human eye. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
May 1999 Dust Storm in Valle
PIA02045
Sol (our sun)
Mars Orbiter Camera
Title |
May 1999 Dust Storm in Valles Marineris |
Original Caption Released with Image |
Mars Global Surveyor's (MGS) Mars Orbiter Camera (MOC) captured this view of a dust storm within the Ius and Melas Chasms of the Valles Marineris trough system on May 16, 1999. The dust storm is seen in the lower 1/3 of the image. It occurs at the junction between eastern Ius Chasma and western Melas Chasma. The apparent motion of the storm is approximately from the south (bottom of image) toward the north. The dust cloud forms a sharp front along its northern margin, which is seen along the north wall of Ius and Melas Chasms--in fact, at the time the image was taken, the dust had advanced up over the north wall of Melas Chasma (upper portion of lower right third of image) and was advancing across the upland that separates this chasm from western Candor Chasma. For a clear-atmosphere view of western Candor and Melas Chasms, see "Western Melas and Candor Chasms, Valles Marineris, MOC2-105, 25 March 1999" [ http://www.msss.com/mars/global_surveyor/camera/images/3_25_99_vmcolor/index.html ]. For scale, note that the large crater south of Hebes Chasma, Perrotin, is about 95 kilometers (59 miles) across. Bluish-white clouds in the image are interpreted to consist of water ice. The pink/red clouds of the dust storm occur closer to the ground, at a lower altitude than the water ice clouds. One of the most interesting aspects of this dust storm is that Valles Marineris was observed to have a dust storm at exactly the same time of year, one Martian year ago. During its approach to Mars, MOC obtained a picture of the planet on July 2,1997, just prior to the Mars Pathfinder landing. At the time, it was winter in the southern hemisphere, and dust clouds were observed within Valles Marineris. The picture is seen in "Mars Orbiter Camera Views Mars Pathfinder Landing Site,MOC2-1, 3 July 1997" [ http://www.msss.com/mars/global_surveyor/camera/images/c9/index.html ]. It will be interesting to see if similar storms occur within the Valles Marineris 1 and 2 Mars years hence. The next times will be in early April 2001 and mid-February 2003. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
Mars and Acidalia
Title |
Mars and Acidalia |
Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained four images, which, together, show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered near the location of the Pathfinder landing site. Dark sand dunes that surround the polar cap merge into a large, dark region called Acidalia. This area, as shown by images from the Hubble telescope and other spacecraft, is composed of dark, sand-sized grains of pulverized volcanic rock. Below and to the left of Acidalia are the massive Martian canyon systems of Valles Marineris, some of which form long linear markings that were once thought by some to be canals. Early morning clouds can be seen along the left limb of the planet, and a large cyclonic storm composed of water ice is churning near the polar cap. |
Date |
06/30/1999 |
NASA Center |
Hubble Space Telescope Center |
|
Changes Over a Martian Year
title |
Changes Over a Martian Year -- New Dark Slope Streaks in Lycus Sucli |
Description |
Now in its Extended Mission, Mars Global Surveyor (MGS) is into its second Mars year of systematic observations of the red planet. With the Extended Mission slated to run through April 2002, the Mars Orbiter Camera (MOC) is being used, among other things, to look for changes that have occurred in the past martian year. Because Mars is farther from the Sun than Earth, its year is longer---about 687 Earth days. The two pictures shown here cover the same portion of Lycus Sulci, a rugged, ridged terrain north of the giant Olympus Mons volcano. The interval between the pictures span 92% of a martian year (August 2, 1999 to April 27, 2001). Dark streaks considered to result from the avalanching of dry, fine, bright dust are seen in both images. The disruption of the surface by the avalanching materials is thought to cause them to appear darker than their surroundings, just as the 1997 bouncing of Mars Pathfinder's airbags and the tire tracks made by the Sojourner rover left darkened markings indicating where the martian soil had been disrupted and disturbed. The arrows in the April 2001 picture indicate eight new streaks that formed on these slopes in Lycus Sulci since August 1999. These observations suggest that a new streak forms approximately once per martian year per kilometer (about 0.62 miles) along a slope. In both images, north is toward the top/upper right and sunlight illuminates each from the left. Dark (as well bright) slope streaks are most common in the dust-covered martian regions of Tharsis, Arabia, and Elysium. Additional examples of dark slope streaks can be seen in the following earlier MOC image media releases: * "Recent Movements: New Landslides in Less than 1 Martian Year," March 12, 2000 [ http://www.msss.com/mars_images/moc/lpsc2000/3_00_massmovement/ ] * "Dark Slope Streaks on Elysium Basin Buttes," July 19, 1999 [ http://www.msss.com/mars_images/moc/7_19_99_fifthMars/18_slopes/ ] Images Credit: NASA/JPL/Malin Space Science Systems |
|
Highest-Resolution View of "
PIA03225
Sol (our sun)
Mars Orbiter Camera
Title |
Highest-Resolution View of "Face on Mars |
Original Caption Released with Image |
A key aspect of the Mars Global Surveyor (MGS) Extended Mission is the opportunity to turn the spacecraft and point the Mars Orbiter Camera (MOC) at specific features of interest. A chance to point the spacecraft comes about ten times a week. Throughout the Primary Mission (March 1999 - January 2001), nearly all MGS operations were conducted with the spacecraft pointing "nadir"--that is, straight down. In this orientation, opportunities to hit a specific small feature of interest were in some cases rare, and in other cases non-existent. In April 1998, nearly a year before MGS reached its Primary Mission mapping orbit, several tests of the spacecraft's ability to be pointed at specific features was conducted with great success (e.g., Mars Pathfinder landing site, Viking 1 site, and Cydonia landforms). When the Mars Polar Lander was lost in December 1999, this capability was again employed to search for the missing lander. Following the lander search activities, a plan to conduct similar off-nadir observations during the MGS Extended Mission was put into place. The Extended Mission began February 1, 2001. On April 8, 2001, the first opportunity since April 1998 arose to turn the spacecraft and point the MOC at the popular "Face on Mars" feature. Viking orbiter images acquired in 1976 showed that one of thousands of buttes, mesas, ridges, and knobs in the transition zone between the cratered uplands of western Arabia Terra and the low, northern plains of Mars looked somewhat like a human face. The feature was subsequently popularized as a potential "alien artifact" in books, tabloids, radio talk shows, television, and even a major motion picture. Given the popularity of this landform, a new high-resolution view was targeted by pointing the spacecraft off-nadir on April 8, 2001. On that date at 20:54 UTC (8:54 p.m., Greenwich time zone), the MGS was rolled 24.8° to the left so that it was looking at the "face" 165 km to the side from a distance of about 450 km. The resulting image has a resolution of about 2 meters (6.6 feet) per pixel. If present on Mars, objects the size of typical passenger jet airplanes would be distinguishable in an image of this scale. The large "face" picture covers an area about 3.6 kilometers (2.2 miles) on a side. Sunlight illuminates the images from the left/lower left. |
|
A Closer Encounter with Mars
Title |
A Closer Encounter with Mars |
|
New Views of Mars from the T
PIA02320
Sol (our sun)
Thermal Emission Spectromete
Title |
New Views of Mars from the Thermal Emission Spectrometer Instrument |
Original Caption Released with Image |
During the first 1500 orbits (March through August, 1999) of the Mars Global Surveyor (MGS) mapping mission the Thermal Emission Spectrometer(TES) instrument has been measuring the surface brightness (albedo) of Mars. In this figure of all of the TES data acquired during that period have been combined to produce a detailed image of the Martian surface. The region shown includes the equatorial region of Mars where both the Pathfinder and Viking 1 spacecraft landed. The dark regions are areas swept free of dust by the Martian winds, whereas the brighter regions are areas of dust accumulation. These bright and dark markings are known to change over time as the Martian winds move dust and sand across the surface. The TES measurements are providing a means of tracking these changes in very precise manner. Note that the Pathfinder landing site is located near the boundary between bright and dark regions and that the landing site is located in a region of modest dust accumulation. The TES instrument was built by Raytheon Santa Barbara Remote Sensing and is operated at Arizona State University as part of NASA*s Mars Global Surveyor mission. The MGS mission is managed by the Jet Propulsion Laboratory in Pasadena, CA and operated in conjunction with Lockheed Martin Astronautics in Denver, CO. |
|
Highest-Resolution View of "
title |
Highest-Resolution View of "Face on Mars |
Description |
A key aspect of the Mars Global Surveyor (MGS) Extended Mission is the opportunity to turn the spacecraft and point the Mars Orbiter Camera (MOC) at specific features of interest. A chance to point the spacecraft comes about ten times a week. Throughout the Primary Mission (March 1999 - January 2001), nearly all MGS operations were conducted with the spacecraft pointing "nadir"---that is, straight down. In this orientation, opportunities to hit a specific small feature of interest were in some cases rare, and in other cases non-existent. In April 1998, nearly a year before MGS reached its Primary Mission mapping orbit, several tests of the spacecraft's ability to be pointed at specific features was conducted with great success (e.g., Mars Pathfinder landing site, Viking 1 site, and Cydonia landforms). When the Mars Polar Lander was lost in December 1999, this capability was again employed to search for the missing lander. Following the lander search activities, a plan to conduct similar off-nadir observations during the MGS Extended Mission was put into place. The Extended Mission began February 1, 2001. On April 8, 2001, the first opportunity since April 1998 arose to turn the spacecraft and point the MOC at the popular "Face on Mars" feature. Viking orbiter images acquired in 1976 showed that one of thousands of buttes, mesas, ridges, and knobs in the transition zone between the cratered uplands of western Arabia Terra and the low, northern plains of Mars looked somewhat like a human face. The feature was subsequently popularized as a potential "alien artifact" in books, tabloids, radio talk shows, television, and even a major motion picture. Given the popularity of this landform, a new high-resolution view was targeted by pointing the spacecraft off-nadir on April 8, 2001. On that date at 20:54 UTC (8:54 p.m., Greenwich time zone), the MGS was rolled 24.8° to the left so that it was looking at the "face" 165 km to the side from a distance of about 450 km. The resulting image has a resolution of about 2 meters (6.6 feet) per pixel. If present on Mars, objects the size of typical passenger jet airplanes would be distinguishable in an image of this scale. An earlier picture obtained in June 2000 was combined with the new, April 2001 image, to produce a stereo ("3-D") view of the western portion of the hill ("3-D" glasses with red for left eye and blue for right eye are needed to view the anaglyph). The large "face" picture, above, covers an area about 3.6 kilometers (2.2 miles) on a side, the 3-D picture [ http://www.msss.com/mars_images/moc/extended_may2001/face/index.html ] is about 1 km (0.62 mi) wide. Sunlight illuminates the images from the left/lower left. Images Credit: NASA/JPL/Malin Space Science Systems |
|
1.5 Meter Per Pixel View of
PIA01674
Sol (our sun)
Mars Orbiter Camera
Title |
1.5 Meter Per Pixel View of Boulders in Ganges Chasma |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) on board the Mars Global Surveyor (MGS)spacecraft was designed to be able to take pictures that "bridge the gap" between what could be seen by the Mariner 9 and Viking Orbiters from space and what could be seen by landers from the ground. In other words, MOC was designed to be able to see boulders of sizes similar to and larger than those named "Yogi" at the Mars Pathfinder site and "Big Joe" at the Viking 1 landing site. To see such boulders, a resolution of at least 1.5 meters (5 feet) per pixel was required. With the start of the MGS Mapping Phase of the mission during the second week of March 1999, the MOC team is pleased to report that "the gap is bridged." This image shows a field of boulders on the surface of a landslide deposit in Ganges Chasma. Ganges Chasma is one of the valleys in the Valles Marineris canyon system. The image resolution is 1.5 meters per pixel. The boulders shown here range in size from about 2 meters (7 feet) to about 20 meters (66 feet) in size. The image covers an area 1 kilometer (0.62 miles) across, and illumination is from the upper left. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
Mars Exploration Rover (MER-
PIA05251
Sol (our sun)
Mars Orbiter Camera
Title |
Mars Exploration Rover (MER-B) Opportunity Landing Site |
Original Caption Released with Image |
1, Viking 2, Mars Pathfinder, and Spirit sites. Sunlight illuminates the wide and narrow angle views, and each image in the mosaic, from the left. The THEMIS instrument is operated by a team at Arizona State University, [ http://themis.asu.edu/ ] the THEMIS-VIS camera was built by Malin Space Science Systems (MSSS), [ http://www.msss.com/press_releases/vismoc/ ] which also operates the MGS MOC. Opportunity will land in the mid-afternoon, local time, on Mars. At the same time, Mars Global Surveyor will pass over the site and listen for a transmission of Opportunity's entry, descent, and landing data. These data will be relayed back to Earth by the MOC. For more information about the Mars Exploration Rovers, visit NASA/JPL's Mars Exploration Program Web site. [ http://marsweb.jpl.nasa.gov/ ] For more information about the work that Malin Space Science Systems and MGS MOC are doing in support of the rover missions, see: http://www.msss.com/mer_mission/ [ http://www.msss.com/mer_mission/ ]. For information about how MSSS will use this mosaic of the landing site to help find Opportunity after it touches down, see Finding MERs [ http://www.msss.com/mer_mission/finding_mer/ ]. MER landing site weather reports are located at: http://www.msss.com/mars_images/moc/mer_weather/. [ http://www.msss.com/mars_images/moc/mer_weather/ ], Mosaic (Click on image for larger view) Wide Angle View (Click on image for larger view), Narrow Angle View (Click on image for larger view) 24 January 2004 The second Mars Exploration Rover (MER-B), Opportunity, is set to land on Mars around 9:05 p.m. Pacific Standard Time today, 24 January 2004 (25 January 2004 UTC). Above are shown three perspectives on the Opportunity landing site, which is an ellipse in Meridiani Planum approximately 87 km (54 mi) long by 11 km (6.8 mi) wide. All images are oriented with north up and east to the right. The lander will be coming through the atmosphere from the west/southwest, roughly following the long axis of the ellipse. It is most likely to touch down somewhere near the center of the ellipse. The first image (top) is a mosaic of MGS MOC and Mars Odyssey Thermal Emission Imaging System visible images (THEMIS-VIS). The THEMIS-VIS instrument provides pictures with a spatial resolution of 18 meters per pixel (~59 ft/pixel), the MOC images used in the mosaic have resolutions ranging from 1.4 m/pixel to 12 m/pixel. A total of 15 THEMIS-VIS images were used to form the background, on which 61 MOC high resolution images were mosaiced. These data were acquired over a period spanning parts of 3 Mars years between April 1999 through January 2004. These pictures were acquired not only in different years, but in different seasons, so the illumination angle, overall brightness, and patterns of ephemeral windblown dust and, in some cases, dark dust devil streaks, are different from image to image within the mosaic. The second image (middle) is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle view obtained in November 2003 as part of an on-going effort to monitor the weather at the landing site. The wide angle view provides a sense of the regional context. The third image (bottom) is a 1.8 m/pixel (6 ft/pixel) view near the center of the landing ellipse. It was also acquired by MOC in November 2003, and covers an area 3 km (1.9 mi) wide. The light-toned, somewhat circular features are believed to be either the location of ancient, buried, nearly-filled meteor impact craters or the eroded remains of craters that formed in bedrock that has long since been removed from the region. The Opportunity landing site in Meridiani Planum was selected to provide access, it is hoped, to materials bearing the iron oxide mineral, hematite. Hematite was detected in this region by the Thermal Emission Spectrometer (TES) on MGS. This mineral is suspected of providing a clue that liquid water may have once played a role in the region. The dark-toned materials of Meridiani Planum cover a lighter-toned substrate that may consist of layered rock. Small ridges have formed in the dark material in some parts of the landing ellipse, but no one will know until the first images are returned, exactly what features will be present at the Opportunity site. One thing is certain: no previous Mars lander has ever gone to a setting like Meridiani Planum. The landscape is almost certain to be different than the Viking |
|
Mars Exploration Rover (MER-
PIA05251
Sol (our sun)
Mars Orbiter Camera
Title |
Mars Exploration Rover (MER-B) Opportunity Landing Site |
Original Caption Released with Image |
1, Viking 2, Mars Pathfinder, and Spirit sites. Sunlight illuminates the wide and narrow angle views, and each image in the mosaic, from the left. The THEMIS instrument is operated by a team at Arizona State University, [ http://themis.asu.edu/ ] the THEMIS-VIS camera was built by Malin Space Science Systems (MSSS), [ http://www.msss.com/press_releases/vismoc/ ] which also operates the MGS MOC. Opportunity will land in the mid-afternoon, local time, on Mars. At the same time, Mars Global Surveyor will pass over the site and listen for a transmission of Opportunity's entry, descent, and landing data. These data will be relayed back to Earth by the MOC. For more information about the Mars Exploration Rovers, visit NASA/JPL's Mars Exploration Program Web site. [ http://marsweb.jpl.nasa.gov/ ] For more information about the work that Malin Space Science Systems and MGS MOC are doing in support of the rover missions, see: http://www.msss.com/mer_mission/ [ http://www.msss.com/mer_mission/ ]. For information about how MSSS will use this mosaic of the landing site to help find Opportunity after it touches down, see Finding MERs [ http://www.msss.com/mer_mission/finding_mer/ ]. MER landing site weather reports are located at: http://www.msss.com/mars_images/moc/mer_weather/. [ http://www.msss.com/mars_images/moc/mer_weather/ ], Mosaic (Click on image for larger view) Wide Angle View (Click on image for larger view), Narrow Angle View (Click on image for larger view) 24 January 2004 The second Mars Exploration Rover (MER-B), Opportunity, is set to land on Mars around 9:05 p.m. Pacific Standard Time today, 24 January 2004 (25 January 2004 UTC). Above are shown three perspectives on the Opportunity landing site, which is an ellipse in Meridiani Planum approximately 87 km (54 mi) long by 11 km (6.8 mi) wide. All images are oriented with north up and east to the right. The lander will be coming through the atmosphere from the west/southwest, roughly following the long axis of the ellipse. It is most likely to touch down somewhere near the center of the ellipse. The first image (top) is a mosaic of MGS MOC and Mars Odyssey Thermal Emission Imaging System visible images (THEMIS-VIS). The THEMIS-VIS instrument provides pictures with a spatial resolution of 18 meters per pixel (~59 ft/pixel), the MOC images used in the mosaic have resolutions ranging from 1.4 m/pixel to 12 m/pixel. A total of 15 THEMIS-VIS images were used to form the background, on which 61 MOC high resolution images were mosaiced. These data were acquired over a period spanning parts of 3 Mars years between April 1999 through January 2004. These pictures were acquired not only in different years, but in different seasons, so the illumination angle, overall brightness, and patterns of ephemeral windblown dust and, in some cases, dark dust devil streaks, are different from image to image within the mosaic. The second image (middle) is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle view obtained in November 2003 as part of an on-going effort to monitor the weather at the landing site. The wide angle view provides a sense of the regional context. The third image (bottom) is a 1.8 m/pixel (6 ft/pixel) view near the center of the landing ellipse. It was also acquired by MOC in November 2003, and covers an area 3 km (1.9 mi) wide. The light-toned, somewhat circular features are believed to be either the location of ancient, buried, nearly-filled meteor impact craters or the eroded remains of craters that formed in bedrock that has long since been removed from the region. The Opportunity landing site in Meridiani Planum was selected to provide access, it is hoped, to materials bearing the iron oxide mineral, hematite. Hematite was detected in this region by the Thermal Emission Spectrometer (TES) on MGS. This mineral is suspected of providing a clue that liquid water may have once played a role in the region. The dark-toned materials of Meridiani Planum cover a lighter-toned substrate that may consist of layered rock. Small ridges have formed in the dark material in some parts of the landing ellipse, but no one will know until the first images are returned, exactly what features will be present at the Opportunity site. One thing is certain: no previous Mars lander has ever gone to a setting like Meridiani Planum. The landscape is almost certain to be different than the Viking |
|
Mars Exploration Rover (MER-
PIA05251
Sol (our sun)
Mars Orbiter Camera
Title |
Mars Exploration Rover (MER-B) Opportunity Landing Site |
Original Caption Released with Image |
1, Viking 2, Mars Pathfinder, and Spirit sites. Sunlight illuminates the wide and narrow angle views, and each image in the mosaic, from the left. The THEMIS instrument is operated by a team at Arizona State University, [ http://themis.asu.edu/ ] the THEMIS-VIS camera was built by Malin Space Science Systems (MSSS), [ http://www.msss.com/press_releases/vismoc/ ] which also operates the MGS MOC. Opportunity will land in the mid-afternoon, local time, on Mars. At the same time, Mars Global Surveyor will pass over the site and listen for a transmission of Opportunity's entry, descent, and landing data. These data will be relayed back to Earth by the MOC. For more information about the Mars Exploration Rovers, visit NASA/JPL's Mars Exploration Program Web site. [ http://marsweb.jpl.nasa.gov/ ] For more information about the work that Malin Space Science Systems and MGS MOC are doing in support of the rover missions, see: http://www.msss.com/mer_mission/ [ http://www.msss.com/mer_mission/ ]. For information about how MSSS will use this mosaic of the landing site to help find Opportunity after it touches down, see Finding MERs [ http://www.msss.com/mer_mission/finding_mer/ ]. MER landing site weather reports are located at: http://www.msss.com/mars_images/moc/mer_weather/. [ http://www.msss.com/mars_images/moc/mer_weather/ ], Mosaic (Click on image for larger view) Wide Angle View (Click on image for larger view), Narrow Angle View (Click on image for larger view) 24 January 2004 The second Mars Exploration Rover (MER-B), Opportunity, is set to land on Mars around 9:05 p.m. Pacific Standard Time today, 24 January 2004 (25 January 2004 UTC). Above are shown three perspectives on the Opportunity landing site, which is an ellipse in Meridiani Planum approximately 87 km (54 mi) long by 11 km (6.8 mi) wide. All images are oriented with north up and east to the right. The lander will be coming through the atmosphere from the west/southwest, roughly following the long axis of the ellipse. It is most likely to touch down somewhere near the center of the ellipse. The first image (top) is a mosaic of MGS MOC and Mars Odyssey Thermal Emission Imaging System visible images (THEMIS-VIS). The THEMIS-VIS instrument provides pictures with a spatial resolution of 18 meters per pixel (~59 ft/pixel), the MOC images used in the mosaic have resolutions ranging from 1.4 m/pixel to 12 m/pixel. A total of 15 THEMIS-VIS images were used to form the background, on which 61 MOC high resolution images were mosaiced. These data were acquired over a period spanning parts of 3 Mars years between April 1999 through January 2004. These pictures were acquired not only in different years, but in different seasons, so the illumination angle, overall brightness, and patterns of ephemeral windblown dust and, in some cases, dark dust devil streaks, are different from image to image within the mosaic. The second image (middle) is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle view obtained in November 2003 as part of an on-going effort to monitor the weather at the landing site. The wide angle view provides a sense of the regional context. The third image (bottom) is a 1.8 m/pixel (6 ft/pixel) view near the center of the landing ellipse. It was also acquired by MOC in November 2003, and covers an area 3 km (1.9 mi) wide. The light-toned, somewhat circular features are believed to be either the location of ancient, buried, nearly-filled meteor impact craters or the eroded remains of craters that formed in bedrock that has long since been removed from the region. The Opportunity landing site in Meridiani Planum was selected to provide access, it is hoped, to materials bearing the iron oxide mineral, hematite. Hematite was detected in this region by the Thermal Emission Spectrometer (TES) on MGS. This mineral is suspected of providing a clue that liquid water may have once played a role in the region. The dark-toned materials of Meridiani Planum cover a lighter-toned substrate that may consist of layered rock. Small ridges have formed in the dark material in some parts of the landing ellipse, but no one will know until the first images are returned, exactly what features will be present at the Opportunity site. One thing is certain: no previous Mars lander has ever gone to a setting like Meridiani Planum. The landscape is almost certain to be different than the Viking |
|
Mars Exploration Rover (MER-
PIA05251
Sol (our sun)
Mars Orbiter Camera
Title |
Mars Exploration Rover (MER-B) Opportunity Landing Site |
Original Caption Released with Image |
1, Viking 2, Mars Pathfinder, and Spirit sites. Sunlight illuminates the wide and narrow angle views, and each image in the mosaic, from the left. The THEMIS instrument is operated by a team at Arizona State University, [ http://themis.asu.edu/ ] the THEMIS-VIS camera was built by Malin Space Science Systems (MSSS), [ http://www.msss.com/press_releases/vismoc/ ] which also operates the MGS MOC. Opportunity will land in the mid-afternoon, local time, on Mars. At the same time, Mars Global Surveyor will pass over the site and listen for a transmission of Opportunity's entry, descent, and landing data. These data will be relayed back to Earth by the MOC. For more information about the Mars Exploration Rovers, visit NASA/JPL's Mars Exploration Program Web site. [ http://marsweb.jpl.nasa.gov/ ] For more information about the work that Malin Space Science Systems and MGS MOC are doing in support of the rover missions, see: http://www.msss.com/mer_mission/ [ http://www.msss.com/mer_mission/ ]. For information about how MSSS will use this mosaic of the landing site to help find Opportunity after it touches down, see Finding MERs [ http://www.msss.com/mer_mission/finding_mer/ ]. MER landing site weather reports are located at: http://www.msss.com/mars_images/moc/mer_weather/. [ http://www.msss.com/mars_images/moc/mer_weather/ ], Mosaic (Click on image for larger view) Wide Angle View (Click on image for larger view), Narrow Angle View (Click on image for larger view) 24 January 2004 The second Mars Exploration Rover (MER-B), Opportunity, is set to land on Mars around 9:05 p.m. Pacific Standard Time today, 24 January 2004 (25 January 2004 UTC). Above are shown three perspectives on the Opportunity landing site, which is an ellipse in Meridiani Planum approximately 87 km (54 mi) long by 11 km (6.8 mi) wide. All images are oriented with north up and east to the right. The lander will be coming through the atmosphere from the west/southwest, roughly following the long axis of the ellipse. It is most likely to touch down somewhere near the center of the ellipse. The first image (top) is a mosaic of MGS MOC and Mars Odyssey Thermal Emission Imaging System visible images (THEMIS-VIS). The THEMIS-VIS instrument provides pictures with a spatial resolution of 18 meters per pixel (~59 ft/pixel), the MOC images used in the mosaic have resolutions ranging from 1.4 m/pixel to 12 m/pixel. A total of 15 THEMIS-VIS images were used to form the background, on which 61 MOC high resolution images were mosaiced. These data were acquired over a period spanning parts of 3 Mars years between April 1999 through January 2004. These pictures were acquired not only in different years, but in different seasons, so the illumination angle, overall brightness, and patterns of ephemeral windblown dust and, in some cases, dark dust devil streaks, are different from image to image within the mosaic. The second image (middle) is a Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) red wide angle view obtained in November 2003 as part of an on-going effort to monitor the weather at the landing site. The wide angle view provides a sense of the regional context. The third image (bottom) is a 1.8 m/pixel (6 ft/pixel) view near the center of the landing ellipse. It was also acquired by MOC in November 2003, and covers an area 3 km (1.9 mi) wide. The light-toned, somewhat circular features are believed to be either the location of ancient, buried, nearly-filled meteor impact craters or the eroded remains of craters that formed in bedrock that has long since been removed from the region. The Opportunity landing site in Meridiani Planum was selected to provide access, it is hoped, to materials bearing the iron oxide mineral, hematite. Hematite was detected in this region by the Thermal Emission Spectrometer (TES) on MGS. This mineral is suspected of providing a clue that liquid water may have once played a role in the region. The dark-toned materials of Meridiani Planum cover a lighter-toned substrate that may consist of layered rock. Small ridges have formed in the dark material in some parts of the landing ellipse, but no one will know until the first images are returned, exactly what features will be present at the Opportunity site. One thing is certain: no previous Mars lander has ever gone to a setting like Meridiani Planum. The landscape is almost certain to be different than the Viking |
|
Changes Over a Martian Year
PIA03226
Sol (our sun)
Mars Orbiter Camera
Title |
Changes Over a Martian Year -- New Dark Slope Streaks in Lycus Sucli |
Original Caption Released with Image |
Now in its Extended Mission, Mars Global Surveyor (MGS) is into its second Mars year of systematic observations of the red planet. With the Extended Mission slated to run through April 2002, the Mars Orbiter Camera (MOC) is being used, among other things, to look for changes that have occurred in the past martian year. Because Mars is farther from the Sun than Earth, its year is longer--about 687 Earth days. The two pictures shown here cover the same portion of Lycus Sulci, a rugged, ridged terrain north of the giant Olympus Mons volcano. The interval between the pictures span 92% of a martian year (August 2, 1999 to April 27, 2001). Dark streaks considered to result from the avalanching of dry, fine, bright dust are seen in both images. The disruption of the surface by the avalanching materials is thought to cause them to appear darker than their surroundings, just as the 1997 bouncing of Mars Pathfinder's airbags and the tire tracks made by the Sojourner rover left darkened markings indicating where the martian soil had been disrupted and disturbed. The arrows in the April 2001 picture indicate eight new streaks that formed on these slopes in Lycus Sulci since August 1999. These observations suggest that a new streak forms approximately once per martian year per kilometer (about 0.62 miles) along a slope. In both images, north is toward the top/upper right and sunlight illuminates each from the left. Dark (as well bright) slope streaks are most common in the dust-covered martian regions of Tharsis, Arabia, and Elysium. |
|
A Closer Encounter with Mars
Title |
A Closer Encounter with Mars |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
New Cydonia Picture
PIA02092
Sol (our sun)
Mars Orbiter Camera
Title |
New Cydonia Picture |
Original Caption Released with Image |
The Mars Orbiter Camera (MOC) onboard the Mars Global Surveyor (MGS) orbiter, was designed specifically to bridge the gap between what can be seen from orbit in typical Mariner 9 and Viking orbiter images, and what can be seen from the ground by landers such as Viking 1 and Mars Pathfinder. The camera, therefore, takes pictures of extremely high resolution. These images are often comparable to aerial photographs used by geologists when they are exploring Earth. The highest resolution images that can be obtained are in the range of 1.4 to 2.0 meters (4.6 to 6.5 feet) per pixel. Last year, several pictures of a portion of the Cydonia region of Mars were photographed at lower resolution than is now possible in the Mapping Phase of the MGS mission. The Cydonia region is perhaps most "famous" for being the location of a feature that--in Viking Orbiter images--seemed to resemble a human face. Nearby buttes and hills were considered by some to represent a "city." The MGS spacecraft flew over the "famous" Cydonia landforms again--for the first time since April 1998--on June 27, 1999, at 10:53 UTC (Greenwich Time Zone). The new MOC images shown here provide the highest resolution view yet obtained of the "Cydonia city" landforms. The picture at the above left (MOC2-142a), shows the regional context. Cydonia constitutes a transition zone between the cratered highlands of Arabia Terra, and the less-cratered lowlands of Acidalia Planitia. This transition zone contains thousands of mesas and buttes--somewhat like the Monument Valley region along the Arizona/Utah border in North America. The white box shows the location of the new high resolution view of the "city" landforms. The image is a red wide angle context frame obtained by MOC at the same time that the high resolution view was acquired. The picture is illuminated from the lower left, and north is toward the upper right. The picture in the center is a processed version of the new MOC narrow angle camera image of this portion of Cydonia. You can view the full-size image Like the context image (above left), the high resolution view (center) is illuminated from the lower left. North is toward the upper right. Boulders can be seen on some of the hill slopes, and the plains between the hills are rough and pitted. To conserve data in order to account for downtrack position uncertainties, only 1/2 of the MOC sensor was used to acquire this picture (allowing the image to be twice the length): it covers an area that is 1.5 km (0.9 mi) wide. The picture at the above right is the unprocessed MOC image. This what the processed image (center) looked like before it was rotated 180° (so that north is toward the top) and corrected for a 1.5 aspect ratio. The pixel size in the unprocessed image is different in the cross-track (left-right) and down-track(top-bottom) directions, thus making the craters look "squished." The cross-track scale is about 1.5 meters (5 feet) per pixel, while the down-track scale is about 2.25 meters (7.4 feet) per pixel. In the unprocessed image, the illumination is coming from the upper right. You can view this image at full-size (use "Save this link as..." and examine (MOC2-142c 100% Size) or see it via your web-browser at half-size (MOC2-142c 50% Size). For a look at the Cydonia images previously obtained by MGS MOC in 1998, CLICKHERE [ http://www.msss.com/mars/global_surveyor/camera/images/MENUS/cydonia_list.html ]. For a pre-MGS discussion of Viking orbiter images of the "Face on Mars,"CLICKHERE [ http://www.msss.com/education/facepage/face.html ]. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO. |
|
Mars and Elysium
Title |
Mars and Elysium |
Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained these four images, which, together, show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered near another volcanic region known as Elysium. This area shows many small, dark markings that have been observed by the Hubble telescope and other spacecraft to change as a result of the movement of sand and dust across the Martian surface. In the upper left of this image, at high northern latitudes, a large chevron-shaped area of water ice clouds mark a storm front. Along the right limb, a large cloud system has formed around the Olympus Mons volcano. |
Date |
06/30/1999 |
NASA Center |
Hubble Space Telescope Center |
|
Mars and Tharsis
Title |
Mars and Tharsis |
Full Description |
Taking advantage of Mars's closest approach to Earth in eight years, astronomers using NASA's Hubble Space Telescope have taken the space- based observatory's sharpest views yet of the Red Planet. The telescope's Wide Field and Planetary Camera 2 snapped these images between April 27 and May 6, when Mars was 54 million miles (87 million kilometers) from Earth. From this distance the telescope could see Martian features as small as 12 miles (19 kilometers) wide. The telescope obtained four images, which together show the entire planet. Each view depicts the planet as it completes one quarter of its daily rotation. In these views the north polar cap is tilted toward the Earth and is visible prominently at the top of each picture. The images were taken in the middle of the Martian northern summer, when the polar cap had shrunk to its smallest size. During this season the Sun shines continuously on the polar cap. Previous telescopic and spacecraft observations have shown that this summertime "residual" polar cap is composed of water ice, just like Earth's polar caps. These Hubble telescope snapshots reveal that substantial changes in the bright and dark markings on Mars have occurred in the 20 years since the NASA Viking spacecraft missions first mapped the planet. The Martian surface is dynamic and ever changing. Some regions that were dark 20 years ago are now bright red, some areas that were bright red are now dark. Winds move sand and dust from region to region, often in spectacular dust storms. Over long timescales many of the larger bright and dark markings remain stable, but smaller details come and go as they are covered and then uncovered by sand and dust. This image is centered on the region of the planet known as Tharsis, home of the largest volcanoes in the solar system. The bright, ring- like feature just to the left of center is the volcano Olympus Mons, which is more than 340 miles (550 kilometers) across and 17 miles (27 kilometers) high. Thick deposits of fine-grained, windblown dust cover most of this hemisphere. The colors indicate that the dust is heavily oxidized ("rusted"), and millions (or perhaps billions) of years of dust storms have homogenized its composition. Prominent late afternoon clouds along the right limb of the planet can be seen. |
Date |
06/30/1999 |
NASA Center |
Hubble Space Telescope Center |
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Evidence for Recent Liquid W
PIA01041
Sol (our sun)
Mars Orbiter Camera
Title |
Evidence for Recent Liquid Water on Mars: Clues Regarding the Relative Youth of Martian Gullies |
Original Caption Released with Image |
How recent is "recent"? The small martian gullies discovered in Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) pictures of certain craters, troughs, and valleys between latitudes 30° and 70° appear to be geologically young. This means that, on the scale of a planet that is 4.5billion years old, the gullies may be only a few million, or less, years old. The youth of these gullies relative to the history of Mars is indicated by the lack of impact craters--formed by meteors--on the alcoves, channels, or aprons of these features. However, other evidence suggests that the gullies may, in many cases, be much younger than a few million years--in fact, some might be actively seeping water in modern times. The first picture, "Apron Covering Dunes," shows a deep, prominent martian gully in a south-facing wall in Nirgal Vallis near 29.4°S, 39.1°W. Sunlight illuminates the scene from the upper left. At the bottom of the picture is a series of evenly-spaced, almost parallel ridges. These ridges are dunes created by windblown sand. The apron--the fanlike deposit at the lower end of the deep channel--at this location is seen covering some of the dunes. The sand dunes are thus older than the apron of debris that came from the channel. The dune field has no small meteor impact craters on it, so it, like the gully landforms, is geologically young--yet older than the apron. If the dunes are active in the modern environment--which is uncertain despite the apparent youth of the dunes--then the apron would have had to form within the past few centuries or less. This picture was taken in September 1999. The second picture, "Apron on Polygons," shows aprons deposited at the base of the south-facing slope in an impact crater at 54.8°S, 342.5°W, in Noachis Terra. The slope and plains surrounding the apron materials have a bumpy pattern of evenly-spaced polygons. Polygonal patterns like this are common in the middle and high latitude regions of Mars, and, like their counterparts in the Arctic and Antarctic regions of Earth, probably form by stresses induced by seasonal and daily freezing and warming cycles of ice in the ground. Such polygons, where found on Earth, are usually only several to tens of thousands of years old, at most. The fact than an apron of debris covers such polygons, and no new polygons have formed on top of the apron, all suggest that the apron--and therefore the gully involved in slope erosion at this location--may be no more than a few tens of thousands of years old, and could be much, much younger. The aprons shown here are from the same July 1999 picture as shown in an accompanying release, "Basic Features of Martian Gullies;" the picture is illuminated from the upper left. The third picture, "Fresh, Dust-free Surfaces," shows a January 2000 view of small, dark channels eroded into one of the gully alcoves found in the "Aerobraking Crater" located at 65°S, 15°W. Two aspects of this picture indicate that two of the processes that contribute, to martian gully formation--liquid water seepage and downslope movement of dry, as well as wet, debris--have probably occurred in the near-recent past. In this case, near-recent could mean "within a few days of when the picture was taken" to "within a few years of when the picture was taken." One aspect is the sharp contrast between dark-toned and light-toned surfaces. On Mars, fine, bright dust can settle out of the atmosphere and eventually coat surfaces so that the contrast between dark and light terrains is hidden from view. There was an experiment on the Sojourner Rover in 1997, for example, that found dust to be settling out of the atmosphere almost all of the time during Mars Pathfinder's 83-day mission. If dust were settling on the alcoves and small channels shown here, they would not appear to be so dark relative to the surrounding, bright, dust-covered terrain. The other attribute of the picture that suggests relative youth is the preponderance of boulders and their sharp, crisp relief which indicates that they have not yet broken into finer debris, nor have they been covered up and mantled by sand or dust. Sunlight illuminates the scene from the upper right. |
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