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Voyager 2 Launch
Title Voyager 2 Launch
Full Description Voyager 2 was launched August 20, 1977, sixteen days before Voyager 1 aboard a Titan-Centaur rocket. Their different flight trajectories caused Voyager 2 to arrive at Jupiter four months later than Voyager 1, thus explaining their numbering. The initial mission plan for Voyager 2 specified visits only to Jupiter and Saturn. The plan was augmented in 1981 to include a visit to Uranus, and again in 1985 to include a flyby of Neptune. After completing the tour of the outer planets in 1989, the Voyager spacecraft began exploring interstellar space. The Voyager mission has been managed by NASA's Office of Space Science and the Jet Propulsion Laboratory.
Date 08/20/1977
NASA Center Kennedy Space Center
Voyager 2 Launch
title Voyager 2 Launch
date 08.20.1977
description Voyager 2 was launched August 20, 1977, sixteen days before Voyager 1 aboard a Titan-Centaur rocket. Their different flight trajectories caused Voyager 2 to arrive at Jupiter four months later than Voyager 1, thus explaining their numbering. The initial mission plan for Voyager 2 specified visits only to Jupiter and Saturn. The plan was augmented in 1981 to include a visit to Uranus, and again in 1985 to include a flyby of Neptune. After completing the tour of the outer planets in 1989, the Voyager spacecraft began exploring interstellar space. The Voyager mission has been managed by NASA's Office of Space Science and the Jet Propulsion Laboratory. *Image Credit*: NASA
Solar System Montage of Voya …
Title Solar System Montage of Voyager Images
Full Description This montage of images taken by the Voyager spacecraft of the planets and four of Jupiter's moons is set against a false-color Rosette Nebula with Earth's moon in the foreground. Studying and mapping Jupiter, Saturn, Uranus, Neptune, and many of their moons, Voyager provided scientists with better images and data than they had ever had before or expected from the program. Although launched sixteen days after Voyager 2, Voyager 1's trajectory was a faster path, arriving at Jupiter in March 1979. Voyager 2 arrived about four months later in July 1979. Both spacecraft were then directed to Saturn with Voyager 1 arriving in November 1980 and Voyager 2 in August 1981. Voyager 2 was then diverted to the remaining gas giants, Uranus in January 1986 and Neptune in August 1989. Data collection continues by both Voyager 1 and 2 as the renamed Voyager Interstellar Mission searches for the edge of the solar wind influence (the heliopause) and exits the Solar System. A shortened list of the discoveries of Voyager 1 and 2 include:the discovery of the Uranian and Neptunian magnetospheres (magnetic environments caused by various types of planet cores), the discovery of twenty-two new satellites including three at Jupiter, three at Saturn, ten at Uranus, and six at Neptune, Io was found to have active volcanism (the only other Solar System body than Earth to be confirmed), Triton was found to have active geyser-like structures and an atmosphere, Auroral Zones (where gases become excited after being hit by solar particles) were discovered at Jupiter, Saturn, and Neptune, Jupiter was found to have rings, Neptune, originally thought to be too cold to support such atmospheric disturbances, had large-scale storms.
Date UNKNOWN
NASA Center Jet Propulsion Laboratory
Voyager Tour Montage
Title Voyager Tour Montage
Full Description This montage of images of the planets visited by Voyager 2 was prepared from an assemblage of images taken by the Voyager 2 spacecraft. The Voyager Project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, California.
Date 08/01/1989
NASA Center Jet Propulsion Laboratory
Neptune and Tritron
Title Neptune and Tritron
Full Description This image was returned by the Voyager 2 spacecraft on July 3, 1989, when it was 76 million kilometers (47 million miles) from Neptune. The planet and its largest satellite, Triton, are captured in the field of view of Voyager's narrow-angle camera through violet, clear and orange filters. Triton appears in the lower right corner at about 5 o'clock relative to Neptune. Measurements from Voyager images show Triton to be between 1,400 and 1,800 kilometers (about 870 to 1,100 miles) in radius with a surface that is about as bright as freshly fallen snow. Because Triton is barely resolved in current narrow-angle images, it is too early to see features on its surface. Scientists believe Triton has at least a small atmosphere of methane and possibly other gases. During its closest approach to Triton on August 25, 1989, Voyager provided high-resolution views of the moon's icy surface and reveal whether Triton's atmosphere has clouds. JPL manages the Voyager Project for NASA's Office of Space Science and Applications, Washington, DC.
Date 07/27/1989
NASA Center Jet Propulsion Laboratory
Voyager 2-N76
This dramatic view of the cr …
8/29/89
Date 8/29/89
Description This dramatic view of the crescents of Neptune and Triton was acquired by Voyager 2 approximately 3 days, 6 and one-half hours after its closest approach to Neptune. The spacecraft is now plunging southward at an angle of 48 degrees to the plane of the ecliptic. This direction, combined with the current season of southern summer in the Neptune system, gives this picture its unique geometry. The spacecraft was at a distance of 4.86 million kilometers (3 million miles) from Neptune when these images were shuttered so the smallest detail discernible is approximately 90 kilometers (56 miles). Color was produced using images taken through the narrow-angle camera's clear, orange and green filters. Neptune does not appear as blue from this viewpoint because the forward scattering nature of its atmosphere is more important than its absorption of red light at this high phase angle (134 degrees).The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
Voyager 2-N77
Voyager 2 obtained this high …
8/29/89
Date 8/29/89
Description Voyager 2 obtained this high-resolution color image of Neptune's large satellite Triton during its close flyby on Aug. 25, 1989. Approximately a dozen individual images were combined to produce this comprehensive view of the Neptune-facing hemisphere of Triton. Fine detail is provided by high-resolution, clear-filter images, with color information added from lower-resolution frames. The large south polar cap at the bottom of the image is highly reflective and slightly pink in color, it may consist of a slowly evaporating layer of nitrogen ice deposited during the previous winter. From the ragged edge of the polar cap northward the satellite's face is generally darker and redder in color. This coloring may be produced by the action of ultraviolet light and magnetospheric radiation upon methane in the atmosphere and surface. Running across this darker region, approximately parallel to the edge of the polar cap, is a band of brighter white material that is almost bluish in color. The underlying topography in this bright band is similar, however to that in the darker, redder regions surrounding it. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. #####
Neptune Hurricanes
title Neptune Hurricanes
date 08.24.1989
description Voyager 2 sent back this stunning image of storms at work in Neptune's windy atmosphere in August 1989. This photograph of Neptune was reconstructed from two images taken by Voyager 2's narrow-angle camera, through the green and clear filters. The image shows three of the features that Voyager 2 photographed during its Neptune flyby. At the north (top) is the Great Dark Spot, accompanied by bright, white clouds that undergo rapid changes in appearance. To the south of the Great Dark Spot is the bright feature that Voyager scientists nicknamed "Scooter." Still farther south is the feature called "Dark Spot 2," which has a bright core. Each feature moves eastward at a different velocity, so it is only occasionally that they appear close to each other, such as at the time this picture was taken. Voyager 2 is the only spacecraft to visit Neptune. *Image Credit*: NASA
Neptune - partial rings
Title Neptune - partial rings
Description One of two new ring arcs, or partial rings, discovered today by NASA's Voyager 2 spacecraft, is faintly visible here just outside the orbit of the Neptunian moon 1989N4, also discovered by Voyager 2 earlier this month. The 155 second exposure taken by Voyager's narrow-angle camera shows the glare of an overexposed Neptune to the right of the moon and ring arc. The two bright streaks below the moon and ring arc are stars. The ring arc is approximately 50,000 kilometers (or 30,000 miles) long. (The second ring arc, not apparent here, is approximately 10,000 kilometers (6,000 miles) long and is associated with the moon 1989N3.) The ring arc, along with 1989N4, orbits about 62,000 kilometers (38,000 miles) from the planet's center, or about 37,000 kilometers (23,000 miles) from the planet's cloud tops. Astronomers have long suspected the existence of such an irregular ring system around Neptune. Data from repeated ground based observations hinted at the existence of irregular strands of partial rings orbiting Neptune. Voyager's photographs of the ring arcs are the first photographic evidence that such a ring system exists. Voyager scientists said the ring arcs may be comprised of debris associated with the nearby moons, or may be the remnants of moons that have been torn apart or ground down through collisions. Close-up studies of the ring arcs by Voyager 2 in coming days should help determine their composition. The Voyager mission is conducted by the Jet Propulsion Laboratory for NASA's Office of Space Science and Applications.
Date 08.11.1989
Neptune - dark oval
PIA01990
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune - dark oval
Original Caption Released with Image The large, dark oval spot in Neptune's atmosphere is just coming into view in this picture returned from the Voyager 2 spacecraft on June 30, 1989. The spacecraft was about 83 million kilometers (51.5 million miles) from Neptune. Voyager scientists are interested in the dark oval cloud system, a very large system similar to Jupiter's Great Red Spot. Contrast of the features in Neptune's atmosphere is similar to that obtained at Saturn at about this same distance and lighting, whereas the features are similar to those seen at Jupiter. The Jet Propulsion Laboratory manages the Voyager Project for NASA's Office of Space Science and Applications.
Nereid
Title Nereid
Description Nereid, the last satellite of Neptune to be discovered before Voyager's recent discoveries, was first seen by Gerard Kuiper in 1949. Until this Voyager 2 image was obtained, all that was known about Nereid was its orbital parameters and intrinsic brightness. This Voyager view of Nereid was obtained on Aug. 24, 1989 at a distance of 4.7 million kilometers (2.9 million miles). With a resolution of 43 kilometers (26.6 miles) per pixel, this image has sufficient detail to show the overall size and albedo. Nereid is about 170 kilometers (105 miles) across and reflects about 12 percent of the incident light. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
Date 08.26.1989
Neptune and Triton
PIA01491
Sol (our sun)
Title Neptune and Triton
Original Caption Released with Image This image was returned by the Voyager 2 spacecraft on July 3, 1989, when it was 76 million kilometers (47 million miles) from Neptune. The planet and its largest satellite, Triton, are captured in the field of view of Voyager's narrow-angle camera through violet, clear and orange filters. Triton appears in the lower right corner at about 5 o'clock relative to Neptune. Recent measurements from Voyager images show Triton to be between 1,400 and 1,800 kilometers (about 870 to 1,100 miles) in radius with a surface that is about as bright as freshly fallen snow. Because Triton is barely resolved in current narrow-angle images, it is too early to see features on its surface. Scientists believe Triton has at least a small atmosphere of methane and possibly other gases. During its closest approach to Triton on August 25, 1989, Voyager should provide high-resolution views of the moon's icy surface and reveal whether Triton's atmosphere has clouds. JPL manages the Voyager Project for NASA's Office of Space Science and Applications.
Uranus - Final Image
PIA00143
Sol (our sun)
Imaging Science Subsystem - …
Title Uranus - Final Image
Original Caption Released with Image This view of Uranus was recorded by Voyager 2 on Jan 25, 1986, as the spacecraft left the planet behind and set forth on the cruise to Neptune Voyager was 1 million kilometers (about 600,000 miles) from Uranus when it acquired this wide-angle view. The picture -- a color composite of blue, green and orange frames -- has a resolution of 140 km (90 mi). The thin crescent of Uranus is seen here at an angle of 153 degrees between the spacecraft, the planet and the Sun. Even at this extreme angle, Uranus retains the pale blue-green color seen by ground-based astronomers and recorded by Voyager during its historic encounter. This color results from the presence of methane in Uranus' atmosphere, the gas absorbs red wavelengths of light, leaving the predominant hue seen here. The tendency for the crescent to become white at the extreme edge is caused by the presence of a high-altitude haze Voyager 2 -- having encountered Jupiter in 1979, Saturn in 1981 and Uranus in 1986 -- will proceed on its journey to Neptune. Closest approach is scheduled for Aug 24, 1989. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
AC89-7001
Photo by Voyager 2 (JPL) Dur …
8/21/89
Description Photo by Voyager 2 (JPL) During August 16 and 17, 1989, the Voyager 2 narrow-angle camera was used to photograph Neptune almost continuously, recording approximately two and one-half rotations of the planet. These images represent the most complete set of full disk Neptune images that the spacecraft will acquire. This picture from the sequence shows two of the four cloud features which have been tracked by the Voyager cameras during the past two months. The large dark oval near the western limb (the left edge) is at a latitude of 22 degrees south and circuits Neptune every 18.3 hours. The bright clouds immediately to the south and east of this oval are seen to substantially change their appearances in periods as short as four hours. The second dark spot, at 54 degrees south latitude near the terminator (lower right edge), circuits Neptune every 16.1 hours. This image has been processed to enchance the visibility of small features, at some sacrifice of color fidelity. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. (JPL Ref: A-34611 Voyager 2-N29)
Date 8/21/89
A89-7015
Photographer : JPL Range : 4 …
8/21/89
Description Photographer : JPL Range : 4.8 million km. ( 3 million miles ) P-34648 This Voyager 2, sixty-one second exposure, shot through clear filters, of Neptunes rings. The Voyager cameras were programmed to make a systematic search of the entire ring system for new material. The previously ring arc is visible as a long bright streak at the bottom of the image. Extening beyond the bright arc is a much fainter component which follows the arc in its orbit. this faint material was also visible leading the ring arc and, in total, covers at least half of the orbit before it becomes too faint to identify. Also visible in this image, is a continuous ring of faint material previously identified as a possible ring arc by Voyager. this continuous ring is located just outside the orbit of the moon 1989N3, which was also discovered by Voyager. This moon is visible as a streak in the lower left. the smear of 1989N3 is due to its own orbital motion during the exposure. Extreme computer processing of this image was made to enhance the extremely faint features of Neptunes moon system. the dark area surrounding the moon as well as the bright corners are due to this special processing.
Date 8/21/89
Voyager 2-N67
These two 591-second exposur …
8/27/89
Date 8/27/89
Description These two 591-second exposures of the rings of Neptune were taken with the clear filter by the Voyager 2 wide-angle camera on Aug. 26, 1989 from a distance of 280,000 kilometers (175,000 miles). The two main rings are clearly visible and appear complete over the region imaged. The time between exposures was one hour and 27 minutes. [During this period the bright ring arcs in the outer bright ring were not visible in either picture (they were unfortunately on the opposite side of the planet for each exposure).] Also visible in this image is the inner faint ring at about 42,000 kilometers (25,000 miles) from the center of Neptune, and the faint band which extends smoothly from the 53,000 kilometer (33,000 miles) ring to roughly halfway between the two bright rings. Both of these newly discovered rings are broad and much fainter than the two narrow rings. These long exposure images were taken while the rings were back-lighted by the sun at a phase angle of 135 degrees. This viewing geometry enhances the visibility of dust and allows fainter, dusty parts of the ring to be seen. The bright glare in the center is due to over-exposure of the crescent of Neptune. The two gaps in the upper part of the outer ring in the image on the left are due to blemish removal in the computer processing. Numerous bright stars are evident in the background. Both bright rings have material throughout their entire orbit, and are therefore continuous. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. #####
Neptune
PIA02210
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune
Original Caption Released with Image This contrast enhanced color picture of Neptune was acquired by Voyager 2 at a range of 14.8 million kilometers (9.2 million miles) on August 14, 1989. It was produced from images taken through the orange, green and violet filters of Voyager's narrow angle camera. As Voyager 2 approaches Neptune, rapidly increasing image resolution is revealing striking new details in the planet's atmosphere, and this picture shows features as small as a few hundred kilometers in extent. Bright, wispy "cirrus type" clouds are seen overlying the Great Dark Spot (GDS) at its southern (lower) margin and over its northwest (upper left) boundary. This is the first evidence that the GDS lies lower in the atmosphere than these bright clouds, which have remained in its vicinity for several months. Increasing detail in global banding and in the south polar region can also be seen, a smaller dark spot at high southern latitudes is dimly visible near the limb at lower left. The Voyager Mission is conducted by the Jet Propulsion Laboratory for NASA's Office of Space Science and Applications.
Neptune - three new satellit …
PIA01991
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune - three new satellites
Original Caption Released with Image This image captured by the Voyager 2 spacecraft was used to confirm the discovery of three new satellites orbiting Neptune. The 46 second exposure was taken by Voyager 2's narrow angle camera through a clear filter on July 30, 1989, when the spacecraft was about 37.3 million kilometers (23.6 million miles) from Neptune. The large globe of the planet itself is severely overexposed and appears pure white. The image has been computer processed to accentuate the new moons, which otherwise would appear little stronger than background noise. The satellite 1989 N1, at right in this frame, was discovered by Voyager 2 in early July 1989. The new satellites confirmed this week are 1989 N2, 1989 N3 and 1989 N4. Each of the moons appears as a small streak, an effect caused by movement of the spacecraft during the long exposure. The new moons occupy nearly circular and equatorial orbits ranging from about 27,300 to 48,300 kilometers (17,000 to 30,000 miles) from Neptune's cloud tops, and are estimated to range in diameter from about 100 to 200 kilometers (about 60 to 125 miles). The Voyager Mission is conducted by the Jet Propulsion Laboratory for NASA's Office of Space Science and Applications.
Neptune's Rings
PIA01493
Sol (our sun)
Title Neptune's Rings
Original Caption Released with Image In Neptune's outermost ring, 39,000 miles out, material mysteriously clumps into three arcs. Voyager 2 acquired this image as it encountered Neptune in August of 1989. JPL manages and controls the Voyager project for NASA's Office of Space Science.
Saturn and its rings
PIA01969
Sol (our sun)
Imaging Science Subsystem - …
Title Saturn and its rings
Original Caption Released with Image Voyager 1 looked back at Saturn on Nov. 16, 1980, four days after the spacecraft flew past the planet, to observe the appearance of Saturn and its rings from this unique perspective. A few of the spokelike ring features discovered by Voyager appear in the rings as bright patches in this image, taken at a distance of 5.3 million kilometers (3.3 million miles) from the planet. Saturn's shadow falls upon the rings, and the bright Saturn crescent is seen through all but the densest portion of the rings. From Saturn, Voyager 1 is on a trajectory taking the spacecraft out of the ecliptic plane, away from the Sun and eventually out of the solar system (by about 1990). Although its mission to Jupiter and Saturn is nearly over (the Saturn encounter ends Dec. 18, 1980), Voyager 1 will be tracked by the Deep Space Network as far as possible in an effort to determine where the influence of the Sun ends and interstellar space begins. Voyager 1's flight path through interstellar space is in the direction of the constellation Ophiuchus. Voyager 2 will reach Saturn on August 25, 1981, and is targeted to encounter Uranus in 1986 and possibly Neptune in 1989. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, California.
Neptune's Great Dark Spot: G …
Title Neptune's Great Dark Spot: Gone But Not Forgotten
Explanation When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were [ http://vraptor.jpl.nasa.gov/voyager/vgrnep_fs.html ] shocked. Since Neptune [ http://nssdc.gsfc.nasa.gov/photo_gallery/ photogallery-neptune.html ] receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images [ http://ic-www.arc.nasa.gov/ic/projects/bayes-group/ Atlas/Voyager/Neptune/by-description/ ] revealed evidence of a dynamic [ http://antwrp.gsfc.nasa.gov/apod/ap010821.html ] and turbulent world. One of the most spectacular discoveries was of the Great Dark Spot [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/ darkspot.txt ], shown here in close-up. Surprisingly, it was comparable in size and at the same relative southern latitude as Jupiter's Great Red Spot [ http://heritage.stsci.edu/public/aug5/displayjupgrs.html ], appearing to be a similar rotating storm system. Winds near the spot were measured up to 1500 miles per hour, the strongest recorded on any planet. The Voyager data also revealed that the Great Dark Spot varied significantly in size during the brief flyby. When the Hubble Space Telescope viewed [ http://www.stsci.edu/pubinfo/PR/95/09.html ] the planet in 1994, the spot had vanished [ http://www.stsci.edu/pubinfo/gif/Neptune.txt ] -- only to be replaced by another dark spot [ http://www.stsci.edu/pubinfo/gif/NeptDS.txt ] in the planet's northern hemisphere!
A89-7042
Photographer: JPL P-34578 BW …
8/11/89
Description Photographer: JPL P-34578 BW One of two new ring arcs, or partial rings, discovered by Voyager 2, is faintly visible just outside the orbit of the Neptunian moon 1989N4.The 155-second exposure taken by the spacecraft's narrow-angle camera shows the glare of an overexposed Neptune to the right of the moon and ring arc. The two bright streaks below the moon and ring arc are stars. The ring arc is approximately 50,000 kilometers (30,000 miles) long. The second ring arc, not apparent here, is about 10,000 kilometers (6,000 miles) long and is assoiciated with moon 1989N3. The ring arc, along with 1989N4, orbits about 62,000 kilometers (38,000 miles) from the planet's cloud tops. Astronomers long suspected the existence of such an irregular ring system around Neptune. Data from repeated ground-based observations hinted at the existence of irregular strands of partial rings orbiting Neptune. Voyager's photographs of the ring arcs are the first photographic evidence that such a ring system exists. Voyager scientists said the ring arcs may be comprised of debris associated with the nearby moons, or may be the remnants of moons that have been torn apart or ground down through collisions. Close-up studies of the ring arcs by Voyager 2 will help determine their composition.
Date 8/11/89
AC89-7010
Voyager II Imagery - Neptune …
8/21/89
Description Voyager II Imagery - Neptune: This image of clouds in Neptune's atmosphere is the first that tests the accuracy of the weather forecast that was made eight days earlier to select targets for the Voyager narrow-angle camera. Three of the four targeted features are visible in this photograph, all three are close to their predicted locations. The Great Dark Spot with its bright white companion is slightly to the left of center. The small bright Scooter is below and to the left, and the second dark spot with its bright core is below the Scooter. Strong eastward winds -- up to 400 mph -- cause the second dark spot to overtake and pass the larger one every five days. The spacecraft was 6.1 million kilometers (3.8 million miles) from the planet at the time of camera shuttering, and the images use the orange, green and clear filters of the camera. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. (JPL ref P-34632 Voyager 2 N-32C)
Date 8/21/89
Neptune's Great Dark Spot: G …
Title Neptune's Great Dark Spot: Gone But Not Forgotten
Explanation When NASA's Voyager 2 spacecraft flew by distant Neptune in August of 1989, astronomers were shocked [ http://vraptor.jpl.nasa.gov/voyager/vgrnep_fs.html ]. Since Neptune [ http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-neptune.html ] receives only 3 percent the sunlight Jupiter does, they expected to find a dormant, dark, frigid planet. Instead, the Voyager images [ http://ic-www.arc.nasa.gov/ic/projects/bayes-group/ Atlas/Voyager/Neptune/by-description/ ] revealed evidence of a dynamic and turbulent world [ http://antwrp.gsfc.nasa.gov/apod/ap960507.html ]. One of the most spectacular discoveries was of the Great Dark Spot [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/darkspot.txt ], shown here in close-up. Surprisingly, it was comparable in size and at the same relative southern latitude as Jupiter's Great Red Spot [ http://antwrp.gsfc.nasa.gov/apod/ap950625.html ], appearing to be a similar rotating storm system. Winds near the spot were measured up to 1500 miles per hour, the strongest recorded on any planet. The Voyager data also revealed that the Great Dark Spot varied [ http://bang.lanl.gov/solarsys/neptune.htm#darkspot ] significantly in size during the brief flyby. When the Hubble Space Telescope viewed [ http://www.stsci.edu/pubinfo/PR/95/09.html ] the planet in 1994, the spot had vanished [ http://www.stsci.edu/pubinfo/gif/Neptune.txt ] -- only to be replaced by another dark spot [ http://www.stsci.edu/pubinfo/gif/NeptDS.txt ] in the planet's northern hemisphere!
AC89-7013
Photographer : JPL P-34648 T …
8/23/89
Description Photographer : JPL P-34648 This photograph of Neptune was reconstructed from two images taken by Voyager 2's narrow angle camera, through the green and clear filters. the image shows three of the features that Voyager 2 has been photographing during recent weeks. At the north ( top ) is the Great Dark Spot, accompanied by bright, white clouds that undergo rapid changes in appearance. to the south of the Great Dark Spot is the bright feature that Voyager scientists have nicknamed "Scooter." Still farther south is the feature called " Dark Spot 2," which has a bright core. Each feature moves eastward at a different at a different velocity, so it is only occasionally that they appear close to each other, such as at the time this picture was taken.
Date 8/23/89
AC89-7055
Vouager II Imagery, Neptune: …
8/25/89
Description Vouager II Imagery, Neptune: This is one of the most detailed views of the surface of Triton taken by Voyager 2 on its flyby of the large satellite of Neptune early in the morning of August 25, 1989. The picture was stored on the tape recorder and relayed to Earth later. Taken from a distanT ce of only 40,000 km (25, 000 miles), the frame is about 220 kilometers (140 miles) across and shows details as small as 750 meters (0.5 miles). Most of the area is covered by a peculiar landscape of roughly circular depressions separated by rugged ridges. This type of terrain, which covers large tracts of Triton's northern hemisphere, is unlike anything seen elsewhere in the solar system. The depressions are probably not impact craters: They are too similar in size and too regularly spaced. Their origin is still unknown, but may involve local melting and collapse of the icy surface. A conspicuous set of grooves and ridges cuts across the landscape, indicating fracturing and deformation of Triton's surface. The rarity of impact craters suggests a young surface by solar-system standards, probably less than a few billion years old. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. (JPL ref: P-34722 Voyager N-60 )
Date 8/25/89
Triton: Neptune's Largest Mo …
Title Triton: Neptune's Largest Moon
Explanation On October 10th, 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well. Lassell soon proved that the ring was a product of his new telescope's distortion, but the satellite Triton remained. The above picture of Triton was taken in 1989 by the only spacecraft ever to pass Triton: Voyager 2. Voyager 2 found fascinating terrain, a thin atmosphere, and even evidence for ice volcanoes on this world of peculiar orbit and spin. Ironically, Voyager 2 also confirmed the existence of complete thin rings around Neptune - but these would have been quite invisible to Lassell!
Triton: Neptune's Largest Mo …
Title Triton: Neptune's Largest Moon
Explanation One hundred and fifty three years ago, on October 10th, 1846, William Lassell was observing the newly discovered planet Neptune [ http://www.seds.org/nineplanets/nineplanets/neptune.html ]. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well. Lassell soon proved that the ring was a product of his new telescope's distortion, but the satellite Triton remained. The above picture [ http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vg2_p34764.html ] of Triton was taken in 1989 by the only spacecraft ever to pass Triton: Voyager 2. Voyager 2 found fascinating terrain [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/triton_close.txt ], a thin atmosphere, and even evidence for ice volcanoes [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ] on this world of peculiar orbit and spin. Ironically, Voyager 2 also confirmed the existence of complete thin rings [ http://nssdc.gsfc.nasa.gov/imgcat/html/object_page/vg2_1135023.html ] around Neptune - but these would have been quite invisible to Lassell!
Neptune: Ring Arcs
PIA02256
Neptune
Imaging Science Subsystem - …
Title Neptune: Ring Arcs
Original Caption Released with Image The Voyager spacecraft was 8.6 million kilometers (5.3 million miles) from Neptune when it took this 61 second exposure through the clear filter with the narrow angle camera on August 19, 1989. The Voyager cameras were programmed to make a systematic search for faint ring arcs and new satellites. The bright upper corner of the image is due to a residual image from a previous long exposure of the planet. The portion of the arc visible here is approximately 35 degrees in longitudinal extent, making it approximately 38,000 kilometers (24,000 miles) in length, and is broken up into three segments separated from each other by approximately 5 degrees. The trailing edge is at the upper right and has an abrupt end while the leading edge seems to fade into the background more gradually. This arc orbits very close to one of the newly discovered Neptune satellites, 1989N4. Close-up studies of this ring arc will be carried out in the coming days which will give higher spatial resolution at different lighting angles. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
Neptune
PIA02205
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune
Original Caption Released with Image This image of the planet Neptune was taken by the Voyager 2spacecraft on January 23, 1989, about seven months before its scheduled August 25 encounter. The spacecraft was 310 million kilometers (192 million miles) from the planet, looking from 34 degrees south of Neptune's equator through the "clear" filter. Similar images from Earth-based telescopes had shown a featureless disk, through red filters, chosen to mark methane gas, revealed irregular-shaped features associated with high-altitude hazes. The Voyager data reveal cloud structure at lower altitudes where the circulation is apparently arranged in parallel east-west bands, as is the case on Jupiter, Saturn, and Uranus. In the original image, the bright bands are about 10 percent brighter than the dark band circling the South pole. This is about the same contrast shown by Saturn, and ten times more than Uranus. The brightening and sawtooth edge around the right side are artifacts of the data processing. The Voyager project is managed by the Jet Propulsion Laboratory for the NASA Office of Space Science and Applications.
Neptune
PIA02209
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune
Original Caption Released with Image These pictures of Neptune were obtained by Voyager 2 on April 26,1989, at a distance of 176 million kilometers (109 million miles). At the center of the Neptune disc, each pixel covers a square 4 degrees by 4 degrees in latitude. (Each Voyager image contains 800 pixels, picture elements, per line and 800 lines.) Resolution here was 3256 kilometers (2020 miles) per line pair. The violet, clear and orange filters of Voyager's narrow-angle camera were used to produce the color pictures. Image processing enhances contrast of the features. The picture on the right was taken five hours after that at left, during which time the planet rotated 100 degrees. The dark spot visible in the left picture appeared in clear filter images obtained three months earlier. A much brighter, white spot, prominent in the earlier images, has now apparently faded. The white spot near the south pole in the right picture is new. It was visible only faintly in a picture taken 18 hours earlier at the same longitude. This evidence of dynamic activity was unexpected in Neptune's atmosphere because Neptune receives only one-tenth of one percent as much solar energy as does the Earth.
Neptune through a clear filt …
PIA01999
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune through a clear filter
Original Caption Released with Image On July 23, 1989, the Voyager 2 spacecraft took this picture of Neptune through a clear filter on its narrow-angle camera. The image on the right has a latitude and longitude grid added for reference. Neptune's Great Dark Spot is visible on the left limb of the planet at about 22.5 degrees south latitude. In previous photographs, less detail was visible, now additional structure associated with the dark spot has become apparent. The jagged right edge of the large spot is real and is probably caused by cloud motion. Voyager 2 was about 47 million kilometers (29 million miles) from Neptune when this picture was taken. The smaller dark spot in the southern dark band is visible on the lower right with a small, light circle at its center. The Jet Propulsion Laboratory manages the Voyager Project for NASA's Office of Space Science and Applications.
Neptune
Title Neptune
Description This contrast enhanced color picture of Neptune was acquired by Voyager 2 at a range of 14.8 million kilometers (9.2 million miles) on August 14, 1989. It was produced from images taken through the orange, green and violet filters of Voyager's narrow angle camera. As Voyager 2 approaches Neptune, rapidly increasing image resolution is revealing striking new details in the planet's atmosphere, and this picture shows features as small as a few hundred kilometers in extent. Bright, wispy "cirrus type" clouds are seen overlying the Great Dark Spot (GDS) at its southern (lower) margin and over its northwest (upper left) boundary. This is the first evidence that the GDS lies lower in the atmosphere than these bright clouds, which have remained in its vicinity for several months. Increasing detail in global banding and in the south polar region can also be seen, a smaller dark spot at high southern latitudes is dimly visible near the limb at lower left. The Voyager Mission is conducted by the Jet Propulsion Laboratory for NASA's Office of Space Science and Applications.
Date 08.17.1989
Neptune Scooter
Title Neptune Scooter
Description This photograph of Neptune was reconstructed from two images taken by Voyager 2's narrow-angle camera, through the green and clear filters. The image shows three of the features that Voyager 2 has been photographing during recent weeks. At the north (top) is the Great Dark Spot, accompanied by bright, white clouds that undergo rapid changes in appearance. To the south of the Great Dark Spot is the bright feature that Voyager scientists have nicknamed "Scooter." Still farther south is the feature called "Dark Spot 2," which has a bright core. Each feature moves eastward at a different velocity, so it is only occasionally that they appear close to each other, such as at the time this picture was taken. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
Date 08.23.1989
Neptune's rings
Title Neptune's rings
Description This wide-angle Voyager 2 image, taken through the camera's clear filter, is the first to show Neptune's rings in detail. The two main rings, about 53,000 km (33,000 miles) and 63,000 km (39,000 miles) from Neptune, are 5 to 10 times brighter than in earlier images. The difference is due to lighting and viewing geometry. In approach images, the rings were seen in light scattered backward toward the spacecraft at a 15-degree phase angle. However, this image was taken at a 135-degree phase angle as Voyager left the planet. That geometry is ideal for detecting microscopic particles that forward-scatter light preferentially. The fact that Neptune's rings are so much brighter at that angle means the particle-size distribution is quite different from most of Uranus' and Saturn's rings, which contain fewer dust-size grains. However, a few components of the Saturnian and Uranian ring systems exhibit forward-scattering behavior: The F ring and the Encke Gap ringlet at Saturn, and 1986U1R at Uranus. They are also narrow, clumpy ringlets with kinks, and are associated with nearby moonlets too small to detect directly. In this image, the main clumpy arc, composed of three features each about 6 to 8 degrees long, is clearly seen. This image was obtained when Voyager was 1.1 million km (683,000 miles) from Neptune. Exposure time was 111seconds. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications.
Date 08.26.1989
Triton - Detail of Dark and …
title Triton - Detail of Dark and Light Material
date 08.24.1989
description Voyager 2 acquired this black and white image of Triton, Neptune's largest satellite, during the night of Aug. 24-25, 1989. Triton's limb cuts obliquely across the middle of the image. The field of view is about 1,000 km (600 miles) across. Three irregular dark areas, surrounded by brighter material, dominate the image. Low-lying material with intermediate albedo occupies the central area, and fresh craters occur along the right margin. Sub-parallel alignment of linear patches of dark material shown in the lower and left part of the image suggests that the patches are structurally controlled. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. *Image Credit*: JPL
Triton
title Triton
date 08.23.1989
description The smallest features that can be seen in this false color image of Neptune's largest satellite, Triton, are about 47 km (29 miles) across. The image, taken by Voyager 2 early in the morning of Aug. 23, 1989, is a composite of three images taken through ultraviolet, green, and violet filters. The image offers an example of the kinds of puzzles scientists face on the eve of an encounter: Mottling in the bright southern hemisphere may be the result of topography, if Triton's crust is predominantly water ice, which is rigid at Triton's surface temperature. Alternatively, the mottling could be due to markings on a smooth surface, if the crust is composed of nitrogen, carbon monoxide, or methane ice, since they are soft at the same temperature. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applications. *Image Credit*: NASA
Neptune
title Neptune
date 08.21.1989
description This picture of Neptune was produced from the last whole planet images taken through the green and orange filters on the Voyager 2 narrow angle camera. The images were taken at a range of 4.4 million miles from the planet, 4 days and 20 hours before closest approach. The picture shows the Great Dark Spot and its companion bright smudge, on the west limb the fast moving bright feature called Scooter and the little dark spot are visible. These clouds were seen to persist for as long as Voyager's cameras could resolve them. North of these, a bright cloud band similar to the south polar streak may be seen. *Image Credit*: NASA
Full-Disk Neptune
title Full-Disk Neptune
date 08.20.1989
description This picture of Neptune was produced from the last whole planet images taken through the green and orange filters on the Voyager 2 narrow angle camera. The images were taken at a range of 4.4 million miles from the planet, 4 days and 20 hours before closest approach. The picture shows the Great Dark Spot and its companion bright smudge, on the west limb the fast moving bright feature called Scooter and the little dark spot are visible. These clouds were seen to persist for as long as Voyager's cameras could resolve them. North of these, a bright cloud band similar to the south polar streak may be seen. *Image Credit*: NASA
Neptune's Rings
title Neptune's Rings
date 08.24.1989
description This 591-second exposure of the rings of Neptune were taken with the clear filter by the Voyager 2 wide-angle camera. The two main rings are clearly visible and appear complete over the region imaged. Also visible in this image is the inner faint ring and the faint band which extends smoothly from the ring roughly halfway between the two bright rings. Both of these newly discovered rings are broad and much fainter than the two narrow rings. The bright glare is due to overexposure of the crescent on Neptune. Numerous bright stars are evident in the background. Both bright rings have material throughout their entire orbit, and are therefore continuous. *Image Credit*: NASA
Global Color Mosaic of Trito …
Title Global Color Mosaic of Triton
Full Description Global color mosaic of Triton, taken in 1989 by Voyager 2 during its flyby of the Neptune system. Color was synthesized by combining high- resolution images taken through orange, violet, and ultraviolet filters, these images were displayed as red, green, and blue images and combined to create this color version. With a radius of 1,350 (839 mi), about 22% smaller than Earth's moon, Triton is by far the largest satellite of Neptune. It is one of only three objects in the Solar System known to have a nitrogen-dominated atmosphere (the others are Earth and Saturn's giant moon, Titan). Triton has the coldest surface known anywhere in the Solar System (38 K, about -391 degrees Farenheit), it is so cold that most of Triton's nitrogen is condensed as frost, making it the only satellite in the Solar System known to have a surface made mainly of nitrogen ice. The pinkish deposits constitute a vast south polar cap believed to contain methane ice, which would have reacted under sunlight to form pink or red compounds. The dark streaks overlying these pink ices are believed to be an icy and perhaps carbonaceous dust deposited from huge geyser-like plumes, some of which were found to be active during the Voyager 2 flyby. The bluish-green band visible in this image extends all the way around Triton near the equator, it may consist of relatively fresh nitrogen frost deposits. The greenish areas include what is called the cataloupe terrain, whose origin is unknown, and a set of "cryovolcanic" landscapes apparently produced by icy-cold liquids (now frozen) erupted from Triton's interior.
Date 05/01/1980
NASA Center Jet Propulsion Laboratory
A89-7058
Voyager II Imagery, Neptune. …
8/24/89
Description Voyager II Imagery, Neptune. This bulls-eye view of Neptune's small dark spot (D2) was obtained by Voyager 2's narrow-angle camera , when Neptune was within 1.1 million km (680,000 miles) of the planet. The smallest structures that can be seen are 20 km (12 miles) across. This unplanned photograph was obtained when the infrared spectrograph was mapping the the highest-resolution view of the feature taken during the flyby. Banding surrounding the feature indicates unseen strong winds, while structues within the bright spot suggest both active upwelling of clouds and rotation about the center. A rotation rate has not yet been measured, but the v-shaped structure near the right edge of the bright area indicates that the spot rotates clockwise. Unlike the Great Red Spot on Jupiter, which rotates counterclockwise, if the D2 spot on Neptune rotates clockwise, the material will be descending in the dark oval region. The fact that infrared data will yield temperature information about the region above the clouds makes this observation especially valuable. The Voyager Mission is conducted by JPL for NASA's Office of Space Science and Applicaitons. (JPL ref: P-34749 Voyager N-71) taken during the flyby. Banding surrounding the feature indicates unseen strong winds, while structures within the bright spot suggest both active upwelling of clouds and rotation about the center. A rotation rate has not yest been measured, but the Vv-sphped
Date 8/24/89
Neptune - dark feature
PIA01992
Sol (our sun)
Imaging Science Subsystem - …
Title Neptune - dark feature
Original Caption Released with Image This clear filter image was acquired by Voyager 2 on August 14, 1989, at a range of 14.8 million kilometers (9.2 million miles). The image shows a dark feature extending westward (left) and northward (up) toward the equator from the Great Dark Spot (GDS). This puzzling phenomenon developed over a relatively short period (three rotations or about 54 hours), and continues to evolve with time. Further study may reveal whether this protrusion represents an actual flow of dark cloud material from the GDS or is a result of atmospheric disturbances associated with the western boundary of the GDS. Bright, wispy "cirrus type" clouds are seen overlying the GDS at its southern (lower) margin and over its northwest (upper left) boundary. This is the first evidence that the GDS lies lower in the atmosphere than the bright clouds, which have remained in its vicinity for several months. Increasing detail in global banding and in the south polar region is also apparent. The Voyager Mission is conducted by the Jet Propulsion Laboratory for NASA's Office of Space Science and Applications.
A89-7012
Photographer : JPL Range : 4 …
8/22/89
Description Photographer : JPL Range : 4 million km (2.5 million miles) Already-intriquing patterns of unknown origin appear on the surgace of Neptune's largest satellite, Trition, in this image from Voyager 2. Voyager images show that Trition's diameter is about 2,720 km (1,690 miles), and that it is one of the brightest objects in the solar system, reflecting about 70 percent of the sunlight that strikes it. THis is the hemisphere of Triton that always faces away from Neptune. The south pole is near the botton of the image. Triton's rotation axis is tilted so that the latitude at the center of the disk is 55 degrees south. Dark regions at the top of the disk extend from roughly the equator to beyond 20 degrees north. The margin between the bright and dark regions varies with longitude around the satellite. The gray, featureless area just to the right of the center of the disk is due to a reseau (reticule mark) in the camera.
Date 8/22/89
A89-7020
Photographer : JPL P-34668 R …
8/23/89
Description Photographer : JPL P-34668 Range : 25 million km. ( 16 million miles ) Smallest Resolvable Feature : 45 km or 28 miles This Voyager 2 image of Neptune, shot with a narrow angle camera, shows the discovery of shadows in Neptune's atmosphere. The shadows cast onto deep cloud banks by smaller elevated clouds. Located at about 68 degrees south latitude, they are the first cloud shadows ever seen by Voyager on any planet. The dark regions adjacent to the small bright clouds are believed to be shadows, because they are on the side of the cloud that is opposite to the incoming sunlight and because they lengthen in places where the sun lies closer to the horizon. Estimates of the height of these discrete clouds above the underlying cloud bank can be obtained by careful analysis of this data.
Date 8/23/89
A89-7021
Photographer : JPL P-34669 R …
8/23/89
Description Photographer : JPL P-34669 Range : 2.6 million km. ( 1.6 million miles ) Smallest Resolvable Feature : 50 km or 31 miles These two Voyager 2 images, shot through clear filters, show the largest of the new moons of Neptune, 1989N1, discovered by Voyager. The satellite, made of dark material that reflects about 6 % of incident sunlight, has an average radius of about 200 kilometers ( 124 miles ) and an irregular shape. Its similiar appearance in the two images shows that the shape seen here is not the result of image noise or smear. This may the largest satellite in the solar system with such an irregular shape. satellite 1989N1 is slightly larger than the previously known small Neptunian moon Nereid but is very much darker.
Date 8/23/89
A89-7024
Photographer : JPL P-34679 R …
8/23/89
Description Photographer : JPL P-34679 Range : 2 million km. ( 1.2 million miles ) In this Voyager 2, wide-angle image, the two main rings of Neptune can be clearly seen. In the lower part of the frame, the originally-announced ring arc, consisting of three distinct features, is visible. This feature covers about 35 degrees of longitude and has yet to be radially resolved in Voyager Images. from higher resolution images it is known that this region contains much more material than the diffuse belts seen elsewhere in its orbit, which seem to encircle the planet. This is consistent with the fact that ground-based observations of stellar occultations by the rings show them to be very broken and clumpy. The more sensitive, wide-angle camera is revealing more widely distributed but fainter material. Each of these rings of material lies just outside of the orbit of a newly discovered moon. One of these moons, 1989N2, may be seen in the upper right corner. The moon is streaked by its orbital motion, whereas the stars in the frame are less smeared. the dark area around the bright moon and star are artifacts of the processing required to bring out the faint rings.
Date 8/23/89
A89-7039
Photographer: JPL P-34712 Ra …
8/26/89
Description Photographer: JPL P-34712 Range: 1.1 million kilometers (683,000 miles) This wide-angle Voyager 2 image, taken through the camera's clear filter, is the first to show Neptune's rings in detail. The two main rings, about 53,000 km (33,000 miles) and 63,000 km (39,000 miles) from Neptune, are 5 to 10 times brighter than in earlier images. The difference is due to lighting and viewing geometry. In approach images, the rings were seen in light scattered backward toward the spacecraft at a 15 _ phase angle. However, this image was taken at a 135 _ phase angle as Voyager left the planet. That geometry is ideal for detecting microscopic particles that forward scatter light preferentially. The fact that Neptune's rings are so much brighter at that angle means the particle-size distribution is quite different from most of Uranus' and Saturn's rings, which contain fewer dust-size grains. However, a few componenets of the Saturian and Uranian ring systems exhibit forward-scattering behavior: The F ring and the Encke Gap ringlet at Saturn and 1986U1R at Uranus. They are also narrow, clumpy ringlets with kinks, and are associated with nearby moonlets too small to detect directly. In this image, the main clumpy arc, composed of three features each about 6 to 8 degrees long, is clearly seen. Exposure time for this image was 111 seconds.
Date 8/26/89
AC89-7044
Photographer : JPL Range : 3 …
8/22/89
Description Photographer : JPL Range : 30 million km. ( 18.6 million miles ) P-34628 C The south pole of Neptune is at the center of this polar projection made from five color images taken by Voyager 2 over the course of one Neptunian day-- about 18 hours. Latitude lines are concentric circles, and the outer circle is at about 15 degrees north latitude. Cloud paterns are organized by the planet's rotation and are generally concentric with the pole . Oval storms, which drift in longitude at relative speeds up to 400 miles an hour, disrupt the circular symmetry. The color composite was made from black and white frames through the Voyager narrow angle camera's clear, orange, and green filters.
Date 8/22/89
Neptune
Title Neptune
Description These pictures of Neptune were obtained by Voyager 2 on April 26,1989, at a distance of 176 million kilometers (109 million miles). At the center of the Neptune disc, each pixel covers a square 4 degrees by 4 degrees in latitude. (Each Voyager image contains 800 pixels, picture elements, per line and 800 lines.) Resolution here was 3256 kilometers (2020 miles) per line pair. The violet, clear and orange filters of Voyager's narrow-angle camera were used to produce the color pictures. Image processing enhances contrast of the features. The picture on the right was taken five hours after that at left, during which time the planet rotated 100 degrees. The dark spot visible in the left picture appeared in clear filter images obtained three months earlier. A much brighter, white spot, prominent in the earlier images, has now apparently faded. The white spot near the south pole in the right picture is new. It was visible only faintly in a picture taken 18 hours earlier at the same longitude. This evidence of dynamic activity was unexpected in Neptune's atmosphere because Neptune receives only one-tenth of one percent as much solar energy as does the Earth.
Date 05.23.1989
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