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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
Uranus
Title Uranus
Full Description This computer enhancement of a Voyager 2 image, emphasizes the high-level haze in Uranus' upper atmosphere. Clouds are obscured by the overlying atmosphere. JPL manages and controls the Voyager project for NASA's Office of Space Science, Washington, DC.
Date 01/01/1986
NASA Center Jet Propulsion Laboratory
Miranda as seen by Voyager 2
Title Miranda as seen by Voyager 2
Full Description Flying by in early 1986, Voyager 2 captured this picture of Miranda, which enabled scientists to study this moon of Uranus in much greater detail than ever before. Discovered in 1948 by Gerard Peter Kuiper, Miranda is named for the daughter of the wily Prospero in Shakespeare's "The Tempest." It is the eleventh known satellite of Uranus and the innermost large moon of Uranus It was necessary that Voyager 2 passed by Miranda, not for scientific reasons, but simply for the gravity assist it needed to go on to Neptune. Due to the position of the entire Solar System, Miranda provided the energy to throw Voyager 2 to Neptune. Before Voyager, Miranda was largely ignored as it is not the largest moon and did not seem to have any other outstanding qualities. Fortunately, however, Voyager passed close enough to Miranda to provide scientists with fascinating photographs that captivated astronomers. About half ice and half rock, Miranda's surface has terraced layers that indicate both older and new surfaces coexisting. Since the mixing of ancient and recent surfaces is rare in planetary geology, scientists have postulated two explanations for the different ages of the numerous valleys and cliffs on Miranda. One theory is that Miranda could have shattered as many as five times and was then reassembled. Another hypothesis is that partly melted ice upwells forced new surfaces to emerge.
Date 01/25/1986
NASA Center Jet Propulsion Laboratory
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.
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.
Rings of Uranus at 1.44 kilo …
Title Rings of Uranus at 1.44 kilometers
Description The outer rings of Uranus are visible in this Voyager 2 image, obtained Jan. 23, 1986, from a distance of 1.44 million kilometers (890,000 miles). The outermost and brightest ring, called epsilon, is visible along with the fainter and narrower delta and gamma rings (from left). This clear-filter, 15-second exposure was shuttered by Voyager's narrow-angle camera. The resolution of this image is about 15 km (9 mi). The epsilon ring is resolved into two bright components separated by a darker lane of material. Voyager scientists believe this is caused by a thinning of the ring material away from the edges of the ring. This image was part of a sequence of pictures designed to search for moons orbiting within the rings and responsible for their narrow appearance. One of two such "shepherd" moons discovered by Voyager -- found Jan. 20 and designated 1986U7 -- is visible as the elongated bright feature midway between the epsilon and delta rings. The moon appears elongated because its orbital motion smeared its image during the long exposure. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.24.1986
Epsilon ring of Uranus
Title Epsilon ring of Uranus
Description Voyager 2 acquired this high-resolution image of the epsilon ring of Uranus on Jan. 23, 1986, from a distance of 1.12 million kilometers (690,000 miles). This clear-filter image from Voyager's narrow-angle camera has a resolution of about 10 km (6 mi). The epsilon ring, approximately 100 km (60 mi) wide at this location, clearly shows a structural variation. Visible here are a broad, bright outer component about 40 km (25 mi) wide, a darker middle region of comparable width, and a narrow, bright inner strip about 15 km (9 mi) wide. The epsilon-ring structure seen by Voyager is similar to that observed from the ground with stellar-occultation techniques. This frame represents the first Voyager image that resolves these features within the epsilon ring. The occasional fuzzy splotches on the outer and inner parts of the ring are artifacts left by the removal of reseau marks (used for making measurements on the image). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.25.1986
Uranus' innermost satellite …
title Uranus' innermost satellite Miranda
date 01.24.1986
description Miranda, innermost of Uranus' large satellites, is seen at close range in this Voyager 2 image, taken Jan. 24, 1986, as part of a high-resolution mosaicing sequence. Voyager was some 36,000 kilometers (22,000 miles) away from Miranda. This clear-filter, narrow-angle image shows an area about 250 km (150 mi) across, at a resolution of about 800 meters (2,600 feet). Two distinct terrain types are visible: a rugged, higher-elevation terrain (right) and a lower, striated terrain. Numerous craters on the rugged, higher terrain indicate that it is older than the lower terrain. Several scarps, probably faults, cut the different terrains. The impact crater in the lower part of this image is about 25 km (15 mi) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory. *Image Credit*: NASA
Uranus' Moon Miranda
Title Uranus' Moon Miranda
Explanation NASA's robot spacecraft Voyager 2 passed the planet Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] and its moons in 1986. While the cloud tops of Uranus [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/uranus.html ] proved to be rather featureless, the surface of Miranda [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/miranda.html ], the innermost of Uranus [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/uranus.html ]' large moons, showed several interesting features. Voyager 2 passed closer to Miranda [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/miranda.html ] than to any Solar System [ http://antwrp.gsfc.nasa.gov/apod/ap950819.html ] body and hence photographed it with the clearest resolution. Miranda's heavily cratered terrain shows grooves like Jupiter [ http://antwrp.gsfc.nasa.gov/apod/ap951208.html ]'s moon Ganymede [ http://antwrp.gsfc.nasa.gov/apod/ap950904.html ] and several valleys and cliffs. Miranda is made of a roughly equal mix of ice and rock. Miranda was discovered by Gerard Kuiper in 1948.
Uranus's Moon Umbriel: A Mys …
Title Uranus's Moon Umbriel: A Mysterious Dark World
Explanation Why is Umbriel so dark? This dark moon reflects only half the light of other Uranus' [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] moons such as Ariel [ http://antwrp.gsfc.nasa.gov/apod/ap960303.html ]. And what is that bright ring at the top? Unfortunately, nobody yet knows. These questions presented themselves when Voyager [ http://vraptor.jpl.nasa.gov/voyager/voyager.html ] 2 passed this satellite of Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] in January 1986. Voyager found an old surface with unusually large craters, and determined Umbriel [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/umbriel.html ]'s composition to be about half ice and half rock. Umbriel [ http://bang.lanl.gov/solarsys/umbriel.htm ] is the fourth largest and third most distant of Uranus' five large moons. Umbriel was discovered in 1851 by William Lassell [ http://www.ast.cam.ac.uk/~naw96/lassell/lassell.htm ].
Hamlet of Oberon
Title Hamlet of Oberon
Explanation What's in a name? [ http://the-tech.mit.edu/Shakespeare/Quotes/bart.RJ.html#22 ] Since 1919, the International Astronomical Union [ http://www.intastun.org ] has been charged with the task [ http://the-tech.mit.edu/Shakespeare/Quotes/bart.LoveLost.html#3 ] of establishing "conventional" nomenclature [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/nomen.html ] for planets, satellites, and surface features. For the remote Uranian system [ http://antwrp.gsfc.nasa.gov/apod/ap971126.html ] of moons, namesakes from Shakespearean works [ http://the-tech.mit.edu/Shakespeare/works.html ] have been chosen. Thus Oberon [ http://antwrp.gsfc.nasa.gov/apod/ap960408.html ], king of the mid-summer night fairies, is also Uranus' most distant and second largest moon [ http://antwrp.gsfc.nasa.gov/apod/ap970111.html ]. Hamlet is the tragically dark, large and princely crater on its surface [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/uranus/obercrat.html ] (right of center). The above image represents known surface features of Oberon [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/oberon.html ] and was constructed by the U.S. Geological Survey (USGS) based on data from NASA's robot explorer Voyager 2 [ http://vraptor.jpl.nasa.gov/voyager/voyager_fs.html ]. In 1986, Voyager 2 flew through the Uranian system [ http://vraptor.jpl.nasa.gov/voyager/vgrur_fs.html ] - so far it has been the only spacecraft to do so [ http://nssdc.gsfc.nasa.gov/imgcat/html/mission_page/ UR_Voyager_2_page1.html ].
Voyager aircraft return from …
Title Voyager aircraft return from non-stop trip around the world
Description The Voyager aircraft circles before landing at Edwards Air Force Base, Edwards, California, to complete it's record breaking, nonstop unfueled flight around the world. The Voyager landed at Edwards at 8:06 a.m. PST Dec. 23, 1986, after a nine-day flight. Richard Rutan and Jeana Yeager piloted the aircraft from a cramped cockpit. Voyager's takeoff weight was more than 10 times the structural weight, but its drag was lower than almost any other powered aircraft. The aircraft's design and light-weight structural materials allowed it to carry an unprecedented amount of fuel on its 25,000 mile flight. Voyager took off from Edwards Dec. 14, and traveled at an average speed of 115.8 mph. The 9 day, 3 minute, 44 sec. flight nearly doubled the previous distance record set in 1962 by a USAF/Boeing B-52H.
Date 12.23.1986
AC86-7014
Photographer : JPL Range : 2 …
1/22/86
Description Photographer : JPL Range : 2.7 million miles (1.7 million miles) P-29497C Tis Voyager 2, false color composite of Uranus demonstrates the usefulness of special filters in the Voyager cameras for revealing the presence of high altitude hazes in Uranus' atmosphere. The picture is a composite of images obtained through the single orange and two methane filters of Voyager's wide angle camera. Orange, short wavelength and long wavelength methane images are displayed, retrospectively, as blue, green, and orange. The pink area centered on the pole is due to the presence of hazes high in the atmosphere that reflect the light before it has traversed a long enough path through the atmosphere to suffer absorbtion by methane gas. The bluest region at mid-latitude represent the most haze free regions on Uranus, thus, deeper cloud levels can be detected in these areas.
Date 1/22/86
Neptune: Big Blue Giant
Title Neptune: Big Blue Giant
Explanation This picture was taken by the Voyager 2 [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] spacecraft in 1986 - the only spacecraft ever to visit Neptune. Neptune [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/neptune.html ] will be the farthest planet from the Sun [ http://antwrp.gsfc.nasa.gov/apod/ap950813.html ] until 1999, when the elliptical orbit of Pluto will cause it to once again resume this status. Neptune [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/neptune.html ], like Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ], is composed mostly of liquid water, methane and ammonia, is surrounded by a thick gas atmosphere of mostly hydrogen and helium, and has many moons and rings. Neptune [ http://nssdc.gsfc.nasa.gov/photo_gallery/photogallery-neptune.html ]'s moon Triton [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ] is unlike any other and has active volcanoes. The nature of Triton [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/triton.html ]'s unusual orbit around Neptune is the focus of much discussion and speculation. Tomorrow's picture: Pluto: The Frozen Planet
Miranda, Chevron, and Alonso
Title Miranda, Chevron, and Alonso
Explanation Miranda [ http://www.seds.org/nineplanets/nineplanets/miranda.html ] is a bizarre world which surely had a tempest [ http://the-tech.mit.edu/Shakespeare/Comedy/tempest/thetempest.html ]uous past. The innermost of the larger Uranian [ http://pds.jpl.nasa.gov/planets/welcome/uranus.htm ] moons, Miranda is almost 300 miles in diameter and was discovered [ http://antwrp.gsfc.nasa.gov/apod/ap971103.html ] in 1948 by American planetary astronomer Gerard Kuiper [ http://sofia.arc.nasa.gov/KAO/home/kuiper_bio.html ]. Examined very closely by the Voyager 2 spacecraft [ http://vraptor.jpl.nasa.gov/voyager/voyager_fs.html ] in 1986, this dark and distant world turned out to be [ http://vraptor.jpl.nasa.gov/voyager/vgrur_fs.html ] quite a surprise [ http://www.pbm.com/~lindahl/music_and_dance.html ]. Miranda was found to display [ http://www.seds.org/nineplanets/nineplanets/pxuranus.html#Miranda ] a unique, bewildering variety of [ http://www.shakespeare.mcgill.ca/resources/ ] terrain leading some to suggest that it has been fractured up to 5 times during its evolution. Along with the famous "chevron" feature, the bright V-shaped area just above center, this composite of the highest resolution images of Miranda shows [ http://www.hawastsoc.org/solar/cap/uranus/vmiranda.htm ] wild juxtapositions of ridges and valleys, older cratered and younger smooth surfaces, and shadowy canyons perhaps 12 miles deep. The large crater (below center) is the 15 mile wide crater Alonso [ http://the-tech.mit.edu/Shakespeare/Comedy/tempest/ thetempest.dp.html ].
Ariel's Densely Pitted Surfa …
Title Ariel's Densely Pitted Surface
Description This mosaic of the four highest-resolution images of Ariel represents the most detailed Voyager 2 picture of this satellite of Uranus. The images were taken through the clear filter of Voyager's narrow-angle camera on Jan. 24, 1986, at a distance of about 130,000 kilometers (80,000 miles). Ariel is about 1,200 km (750 mi) in diameter, the resolution here is 2.4 km (1.5 mi). Much of Ariel's surface is densely pitted with craters 5 to 10 km (3 to 6 mi) across. These craters are close to the threshold of detection in this picture. Numerous valleys and fault scarps crisscross the highly pitted terrain. Voyager scientists believe the valleys have formed over down-dropped fault blocks (graben), apparently, extensive faulting has occurred as a result of expansion and stretching of Ariel's crust. The largest fault valleys, near the terminator at right, as well as a smooth region near the center of this image, have been partly filled with deposits that are younger and less heavily cratered than the pitted terrain. Narrow, somewhat sinuous scarps and valleys have been formed, in turn, in these young deposits. It is not yet clear whether these sinuous features have been formed by faulting or by the flow of fluids. JPL manages the Voyager project for NASA's Office of Space Science.
Date 01.27.1986
Ariel's transecting valleys
Title Ariel's transecting valleys
Description This highest-resolution Voyager 2 view of Ariel's terminator shows a complex array of transecting valleys with super-imposed impact craters. Voyager obtained this clear-filter, narrow-angle view from a distance of 130,000 kilometers (80,000 miles) and with a resolution of about 2.4 km (1.5 mi). Particularly striking to Voyager scientists is the fact that the faults that bound the linear valleys are not visible where they transect one another across the valleys. Apparently these valleys were filled with deposits sometime after they were formed by tectonic processes, leaving them flat and smooth. Sinuous rilles (trenches) later formed, probably by some flow process. Some type of fluid flow may well have been involved in their evolution. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.26.1986
Titania - Highest Resolution …
Title Titania - Highest Resolution Voyager Picture
Description This is the highest-resolution picture of Titania returned by Voyager 2. The picture is a composite of two images taken Jan. 24, 1986, through the clear filter of Voyager's narrow-angle camera. At the time, the spacecraft was 369,000 kilometers (229,000 miles) from the Uranian moon, the resolution was 13 km (8 mi). Titania is the largest satellite of Uranus, with a diameter of a little more than 1,600 km (1,000 mi). Abundant impact craters of many sizes pockmark the ancient surface. The most prominent features are fault valleys that stretch across Titania. They are up to 1,500 km (nearly 1,000 mi) long and as much as 75 km (45 mi) wide. In valleys seen at right-center, the sunward-facing walls are very bright. While this is due partly to the lighting angle, the brightness also indicates the presence of a lighter material, possibly young frost deposits. An impact crater more than 200 km (125 mi) in diameter distinguishes the very bottom of the disk, the crater is cut by a younger fault valley more than 100 km (60 mi) wide. An even larger impact crater, perhaps 300 km (180 mi) across, is visible at top. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.27.1986
Uranus rings
Title Uranus rings
Description Voyager 2 returned this picture of the Uranus rings on Jan. 22, 1986, from a distance of 2.52 million kilometers (1.56 million miles). All nine known rings are visible in this image, a 15-second exposure through the clear filter on Voyager's narrow-angle camera. The rings are quite dark and very narrow. The most prominent and outermost of the nine, called epsilon, is seen at top. The next three in toward Uranus -- called delta, gamma and eta -- are much fainter and more narrow than the epsilon ring. Then come the beta and alpha rings and finally the innermost grouping, known simply as the 4, 5 and 6 rings. The last three are very faint and are at the limit of detection for the Voyager camera. Uranus' rings range in width from about 100 km (60 mi) at the widest part of the epsilon ring to only a few kilometers for most of the others. This image was processed to enhance these narrow features, the bright dots are imperfections on the camera detector. The resolution scale is approximately 50 km (30 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.23.1986
Uranus' largest moon Oberon
Title Uranus' largest moon Oberon
Description Uranus' outermost and largest moon, Oberon, is seen in this Voyager 2 image, obtained Jan. 22, 1986, from a distance of 2.77 million kilometers (1.72 million miles). The clear-filter image, shuttered by Voyager's narrow-angle camera, shows that Oberon displays several distinct highly reflective (high-albedo) patches with low-albedo centers. Some of the bright patches are suggestive of radial patterns that could represent impact craters excavated from an icy surface. On average, Oberon reflects about 20 percent of the incident sunlight. The moon is about 1,600 km (1,000 mi) in diameter, resolution of this image is 51 km (32 mi). It was taken two days before Voyager's closest approach to Oberon, at which point the spacecraft will be about 471,000 km (293,000 mi) away. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.23.1986
Uranus' Moon Ariel: Valley W …
Title Uranus' Moon Ariel: Valley World
Explanation What formed Ariel [ http://bang.lanl.gov/solarsys/ariel.htm ]'s valleys? This question presented itself when Voyager [ http://vraptor.jpl.nasa.gov/voyager/voyager.html ] 2 passed this satellite of Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] in January 1986. Speculation [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1990Icar%2E%2E%2E87%2E%2E110T&db_key=AST ] includes that heating caused by the ancient tides of Uranus caused moonquakes and massive shifting of the moon's surface. In any event, a huge network of sunken valleys was found to cover this frozen moon, and some unknown material now coats the bottoms of many of these channels. Ariel [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ariel.html ] is the second closest to Uranus outside of Miranda [ http://antwrp.gsfc.nasa.gov/apod/ap951224.html ], and is composed of roughly half water ice and half rock. Ariel was discovered by William Lassell [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/help.html#lassell ] in 1851.
Uranus's Moon Oberon: Impact …
Title Uranus's Moon Oberon: Impact World
Explanation Oberon is the most distant and second largest moon of Uranus. Discovered by William Herschel [ http://www.adventure.com/library/encyclopedia/space/herschls.html ] in 1787, the properties of the world remained relatively unknown until the robot spacecraft Voyager [ http://vraptor.jpl.nasa.gov/voyager/voyager.html ] 2 passed it during its flyby of Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] in January 1986. Compared to Uranus' moons Ariel [ http://antwrp.gsfc.nasa.gov/apod/ap960303.html ], Titania [ http://antwrp.gsfc.nasa.gov/apod/ap960304.html ], and Miranda [ http://antwrp.gsfc.nasa.gov/apod/ap951224.html ], Oberon [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/oberon.html ] is heavily cratered, and in this way resembles Umbriel [ http://antwrp.gsfc.nasa.gov/apod/ap960407.html ]. Like all of Uranus' large moons, Oberon [ http://bang.lanl.gov/solarsys/oberon.htm ] is composed of roughly half ice and half rock. Note that Oberon has at least one large mountain, visible on the limb at the lower left, that rises 6 km off the surface.
A86-7022
Photographer: JPL P-29506BW …
1/25/86
Description Photographer: JPL P-29506BW Range: 1.12 million kilometers (690,000 miles) This high-resolution image of the epsilon ring of Uranus is a clear-filter picture from Voyager's narrow-angle camera and has a resolution of about 10 km (6 mi). The epsilon ring, approx. 100 km (60 mi) wide at this location, clearly shows a structural variation. Visible here are a broad, bright outer component about 40 km (25 mi) wide, a darker, middle region of comparable width, and a narrow, bright inner strip about 15 km (9 mi) wide. The epsilon-ring structure seen by Voyager is similiar to that observed from the ground with stellar-occultation techniques. This frame represents the first Voyager image that resolves these features within the epsilon ring. The occasional fuzzy splotches on the outer and innerparts of the ring are artifacts left by the removal of reseau marks (used for making measurements on the image).
Date 1/25/86
A86-7041
Photographer : JPL Range : 2 …
1/24/86
Description Photographer : JPL Range : 236,000 km. ( 147,000 mi. ) Resolution : 33 km. ( 20 mi. ) P-29525B/W This Voyager 2 image reveals a contiuos distribution of small particles throughout the Uranus ring system. This unigue geometry, the highest phase angle at which Voyager imaged the rings, allows us to see lanes of fine dust particles not visible from other viewing angles. All the previously known rings are visible. However, some of the brightest features in the image are bright dust lanes not previously seen. the combination of this unique geometry and a long, 96 second exposure allowed this spectacular observation, acquired through the clear filter if Voyager 2's wide angle camera. the long exposure produced a noticable, non-uniform smear, as well as streaks due to trailed stars.
Date 1/24/86
AC86-7042
Photographer : JPL Range : 1 …
1/24/86
Description Photographer : JPL Range : 1 illion km. ( 600,000 mi. ) Resolution : 140 km. ( 90 mi. ) P-29539C This Voyager 2 image of Uranus was captured as the spacecraft was leaving Uranus behind on its cruise to Neptune. The image is a color composite of three photographs taken through blue, grren, and orange filters. Thin thin crecent seen here is at an angle of 153 degrees between the the spacecraft, the planet, and the sun. Even at this extreme angle, uranus retains the pale blue-green color seen by the ground based astronomers and recorded by Voyager 2 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 cresent to become white at the extreme edge is cased 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 jouney to Neptune. Closest approach is scheduled for August 24, 1989.
Date 1/24/86
Uranus' Far-flung Rings
Title Uranus' Far-flung Rings
Description Uranus' rings, photographed by Voyager 2 as it approached the plane of the Uranian ring system. JPL manages and controls the Voyager project for NASA's Office of Space Science.
Date 01.01.1986
Uranus' Largest Moon: Titani …
Title Uranus' Largest Moon: Titania
Explanation Titania's tortured terrain is a mix of valleys and craters. NASA's interplanetary robot spacecraft Voyager [ http://spacelink.msfc.nasa.gov/NASA.Projects/Planetary.Probes/Voyager/Mission.Summary ] 2 passed this moon of Uranus [ http://antwrp.gsfc.nasa.gov/apod/ap950816.html ] in 1986 and took the above photograph. The photograph was then transmitted back to earth by radio [ http://www.science.uwaterloo.ca/physics/p13news/number_2/maxnew-2.html ]. The valleys of Titania [ http://bang.lanl.gov/solarsys/titania.htm ] resemble those on Ariel [ http://antwrp.gsfc.nasa.gov/apod/ap960303.html ] indicate that Titania underwent some unknown tumultuous resurfacing event in its distant past. Although Titania [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/titania.html ] is Uranus' largest moon, it is still much smaller than Triton [ http://antwrp.gsfc.nasa.gov/apod/ap950805.html ] - the largest moon of Uranus' sister planet Neptune [ http://antwrp.gsfc.nasa.gov/apod/ap950817.html ]. Titania is essentially a large dirty iceball that orbits Uranus - it is composed of about half water-ice and half rock. Titania was discovered by William Hershel [ http://www.dsi.unimi.it/Users/Students/amoroso/sun/fortunes/life-e.html ] in 1787.
Color Voyager 2 Image Showin …
PIA00346
Sol (our sun)
Title Color Voyager 2 Image Showing Crescent Uranus
Original Caption Released with Image This image shows a crescent Uranus, a view that Earthlings never witnessed until Voyager 2 flew near and then beyond Uranus on January 24, 1986. This planet's natural blue-green color is due to the absorption of redder wavelengths in the atmosphere by traces of methane gas. Uranus' diameter is 32,500 miles, a little over four times that of Earth. The hazy blue-green atmosphere probably extends to a depth of around 5,400 miles, where it rests above what is believed to be an icy or liquid mixture (an 'ocean') of water, ammonia, methane, and other volatiles, which in turn surrounds a rocky core perhaps a little smaller than Earth.
Miranda Fractures, Grooves a …
PIA00140
Uranus
Imaging Science Subsystem - …
Title Miranda Fractures, Grooves and Craters
Original Caption Released with Image This Voyager 2 image of Miranda was taken Jan 24, 1986, from a distance of about 31,000 kilometers (19,000 miles), shortly before the spacecraft's closest approach to the Uranian moon. The high resolution of 600 meters (2,000 feet) reveals a bewildering variety of fractures, grooves and craters, as well as features of different albedos (reflectancea). This clear-filter, narrow-angle view encompasses areas of older, heavily cratered terrain with a wide variety of forms. The grooves and troughs reach depths of a few kilometers (or miles) and expose materials of different albedos. The great variety of directions of fractures and troughs, and the different densities of impact craters on them, signify a long, complex geologic evolution of this satellite. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
A86-7011
Photographer : JPL Range : 2 …
1/14/86
Description Photographer : JPL Range : 2.52 million miles (1.56 million miles) P-29481B/W Voyager 2 returned this photograph with all nine known Uranus rings visible from a 15 sec. exposure through the narrow angle camera. The rings are quite dark and very narrow. The most prominent and outermost of the nine, Epsilon, is seen at top. The next three in toward Uranus, called Delta, Gamma, and Eta, are much fainter and more narrow than Epsilon ring. Then come Beta and Alpha rings, and finally, the innermost grouping, known simply as the 4,5, & 6 rings. The last three are very faint and are at the limit of detection for the Voyager camera. Uranus' rings range in width from about 100 km. (60 mi.) at the widest part of the Epsilon ring, to only a few kilometers for most of the others. this iamge was processed to enhance narrow features, the bright dots are imperfections on the camera detector. The resolution scale is about 50 km. (30 mi.)
Date 1/14/86
A86-7030
Photographer: JPL P-29514 BW …
1/24/86
Description Photographer: JPL P-29514 BW Miranda reveals a complex geologic history in this view acquired by Voyager 2 around its closest approach to the Uranian moon. At least three terrain types of different age and geologic style are evident at this resolution of about 700 meters (2,300 feet). Visible in this clear-filter, narrow-angle image are from left: 1) an apparently ancient, cratered terrain consisting of rolling, subdued hills and degraded medium-sized craters, 2) a grooved terrain with linear valleys and ridges developed at the expense of, or replacing, the first terrain type, and 3) a complex terrain seen along the terminator, in which intersecting curvillinear ridges and troughs are abrubtly truncated by the linear, grooved terrain. Voyager scientists believe this third terrain type is intermediate in age between the first two.
Date 1/24/86
A86-7034
PHOTOGRAPHER: JPL P-29518 BW …
1/26/86
Description PHOTOGRAPHER: JPL P-29518 BW Range: 130,000 kilometers (80,000 miles) This highest-resolution Voyager 2 view of Ariel's terminator shows a complex array of transecting valleys with superimposed impact craters. This clear-filter, narrow-angle view has a resolution of about 2.4 km (1.5 mi). Particularly striking to Voyager scientists is the fact that the faults that bound the linear valleys are not visible where they transect one another across the valleys. Apparently these valleys were filled with deposits sometime after they were formed by tectonic processes, leaving them flat and smooth. Sinuous rilles (trenches) later formed, probably by some flow process. Some type of fluid flow may well have been involved in their evolution.
Date 1/26/86
A86-7035
Photographer: JPL P-29519BW …
1/27/86
Description Photographer: JPL P-29519BW Range: 500,000 kilometers (300,000 miles) Several craters are seen on the surface of 1986U1, one of the several small moons of Uranus discovered by Voyager 2. This single image, a clear-filtered, narrow-angle picture with a resolution of about 10 km (6 mi), is the only closeup the spacecraft obtained of any of the new moons. The moon was found December 30, 1985, it was the first and largest of nine satellites discovered by the spacecraft's cameras. This image shows 1986U1 to be a dark, nearly spherical object, with a diameter of about 150 km (90 mi), the dark surface reflects only 7 percent of the incident light. The picture was inserted into the Voyager encounter sequence late in its development.This image has had a complex history, having been recorded on the spacecraft tape recorder and first played back during the late afternoon of its recording. An antenna-pointing problem at one of the Austrailian tracking stations led to the loss of the data, so the image had to be retransmitted.
Date 1/27/86
A86-7036
Photographer: JPL P-29520 BW …
1/27/86
Description Photographer: JPL P-29520 BW Range: 130,000 kilometers (80,000 miles) This mosaic, taken through the clear-filter, narrow-angle camera, of the four highest-resolution images of Ariel represents the most detailed Voyager 2 picture of this satellite of Uranus. Ariel is about 1,200 km (750 mi) in diameter, the resolution here is 2.4 km (1.5 mi). Much of Ariel's surface is densely pitted with craters 5 to 10 km (3 to 6 mi) across. These craters are close to the threshold of detection in this picture. Numerous valleys and fault scarps crisscross the highly pitted terrain. voyager scientists believe the valleys have formed over down-dropped fault blocks (graben), apparently, extensive faulting has occured as a result of expansion and stretching of Ariel's crust. The largest fault valleys, near the terminator at right, as well as a smooth region near the center of this image, have been partly filled with deposits that are younger and less heavily cratered than the pitted terrain. Narrow, somewhat sinuous scarps and valleys have been formed, in turn, in these young deposits. It is not yet clear whether these sinuous features have been formed by faulting or by the flow of fluids.
Date 1/27/86
Titania's Trenches
Title Titania's Trenches
Explanation British astronomer Sir William Herschel [ http://star.arm.ac.uk/history/herschel.html ] discovered Titania and Oberon in January of 1787. He wasn't reading Shakespeare's [ http://the-tech.mit.edu/Shakespeare/works.html ]"A Midsummer Night's Dream" though, he was making the first telescopic observations of moons of the planet Uranus [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/uranus.html ] (a planet which he himself discovered in 1781 [ http://www-groups.dcs.st-and.ac.uk/~history/ HistTopics/Neptune_and_Pluto.html ]). In January of 1986, nearly 200 years later, NASA's robot explorer Voyager 2 became the only spacecraft to visit the remote Uranian [ http://antwrp.gsfc.nasa.gov/apod/ap990531.html ] system [ http://antwrp.gsfc.nasa.gov/apod/ap971103.html ]. Above is Voyager's highest resolution picture of Titania [ http://photojournal.jpl.nasa.gov/cgi-bin/ PIAGenCatalogPage.pl?PIA00039 ], Uranus' largest moon. The picture is a composite of two images recorded from a distance of 229,000 miles. The icy, rocky world [ http://antwrp.gsfc.nasa.gov/apod/ap960304.html ] is seen to be covered with impact craters. A prominent system of fault valleys, some nearly 1,000 miles long, is visible as trench-like features near the terminator (shadow line). Deposits of highly reflective material which may represent frost can be seen along the sun-facing valley walls. The large impact crater near the top, known as Gertrude [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/uranus/titacrat.html ], is about 180 miles across. At the bottom the 60 mile wide fault valley, Belmont Chasma [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/nomen/uranus/titachas.html ], cuts into crater Ursula. Titania itself [ http://wwwflag.wr.usgs.gov/USGSFlag/Space/wall/titania.html ] is 1,000 miles in diameter.
Miranda - High Resolution Mo …
Title Miranda - High Resolution Mosaic
Description This computer-assembled mosaic of Miranda includes many of the high-resolution frames obtained by Voyager 2 during its close flyby of the Uranian moon. Miranda, roughly 500 kilometers (300 miles) in diameter, exhibits varied geologic provinces, seen in this mosaic of clear-filter, narrow-angle images from Jan. 24, 1986. The images were obtained from distances of 30,160 to 40,310 km (18,730 to 25,030 mi), resolution ranges from 560 to 740 meters (1,840 to 2,430 feet). These are among the highest-resolution pictures that Voyager has obtained of any of the new "worlds" it has encountered during its mission. On Miranda, ridges and valleys of one province are cut off against the boundary of the next province. Probable compressional (pushed-together) folded ridges are seen in curvilinear patterns, as are many extensional (pulled-apart) faults. Some of these show very large scarps, or cliffs, ranging from O.5 to 5 km (O.3 to 3 mi) in height -- that is, higher that the walls of the Grand Canyon on Earth. The missing piece of Miranda's surface will be included in a later mosaic once more complicated computer processing can be completed. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.28.1986
Miranda's Geologic History ( …
Title Miranda's Geologic History (variety of terrain)
Description Miranda reveals a complex geologic history in this view, acquired by Voyager 2 on Jan. 24, 1986, around its close approach to the Uranian moon. At least three terrain types of different age and geologic style are evident at this resolution of about 700 meters (2,300 feet). Visible in this clear-filter, narrow-angle image are, from left: (1) an apparently ancient, cratered terrain consisting of rolling, subdued hills and degraded medium-sized craters (2) a grooved terrain with linear valleys and ridges developed at the expense of, or replacing, the first terrain type: and (3) a complex terrain seen along the terminator, in which intersecting curvilinear ridges and troughs are abruptly truncated by the linear, grooved terrain. Voyager scientists believe this third terrain type is intermediate in age between the first two. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.26.1986
Ariel - Highest Resolution C …
Title Ariel - Highest Resolution Color Picture
Description The complex terrain of Ariel is viewed in this image, the best Voyager 2 color picture of the Uranian moon. The individual photos used to construct this composite were taken Jan. 24, 1986, from a distance of 170,000 kilometers (105,000 miles. Voyager captured this view of Ariel's southern hemisphere through the green, blue and violet filters of the narrow-angle camera, the resolution is about 3 km (2 mi). Most of the visible surface consists of relatively intensely cratered terrain transected by fault scarps and fault-bounded valleys (graben). Some of the largest valleys, which can be seen near the terminator (at right), are partly filled with younger deposits that are less heavily cratered. Bright spots near the limb and toward the left are chiefly the rims of small craters. Most of the brightly rimmed craters are too small to be resolved here, although one about 30 km (20 mi) in diameter can be easily distinguished near the center. These bright-rim craters, though the youngest features on Ariel, probably have formed over a long span of geological time. Although Ariel has a diameter of only about 1,200 km (750 mi), it has clearly experienced a great deal of geological activity in the past. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.27.1986
Bright patches on Ariel
Title Bright patches on Ariel
Description Distinct bright patches are visible on Ariel, the brightest of Uranus' five largest satellites. Voyager 2 obtained this image Jan. 22, 1986, from a distance of 2.52 million kilometers (1.56 million miles). The clear-filter image, obtained with the narrow-angle camera, shows a resolution of 47 km (29 miles). Ariel is about 1,300 km (800 mi) in diameter. This image shows several distinct bright areas that reflect nearly 45 percent of the incident sunlight, on average, the satellite displays a reflectivity of about 25-30 percent. The bright areas are probably fresh water ice, perhaps excavated by impacts. The south pole of Ariel is slightly off center of the disk in this view. Voyager 2 will obtain its best views of the satellite on Jan. 24, at a closest-approach distance of 127,000 km (79,000 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.23.1986
Full-disk view of Titania
Title Full-disk view of Titania
Description Voyager 2 obtained this full-disk view of Uranus' moon Titania in the early morning hours of Jan. 24, 1986, from a distance of about 500,000 kilometers (300,000 miles). Many circular depressions -- probably impact craters -- are visible in this clear-filter image returned by the Voyager narrow-angle camera. Other bright spots are distinguished by radiating rays and are probably halo craters that mark relatively more recent impacts. Even more interesting are linear troughs (right) that are probably fault canyons. The troughs break the crust in two directions, an indication of some tectonic extension of Titania's crust. These features indicate that this icy satellite has a dynamic, active interior. Titania is about 1,600 km (1,000 mi) in diameter, the resolution of this image is about 9 km (6 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.25.1986
Titania High-Resolution Colo …
Title Titania High-Resolution Color Composite
Description This high-resolution color composite of Titania was made from Voyager 2 images taken Jan. 24, 1986, as the spacecraft neared its closest approach to Uranus. Voyager's narrow-angle camera acquired this image of Titania, one of the large moons of Uranus, through the violet and clear filters. The spacecraft was about 500,000 kilometers (300,000 miles) away, the picture shows details about 9 km (6 mi) in size. Titania has a diameter of about 1,600 km (1,000 mi). In addition to many scars due to impacts, Titania displays evidence of other geologic activity at some point in its history. The large, trenchlike feature near the terminator (day-night boundary) at middle right suggests at least one episode of tectonic activity. Another, basinlike structure near the upper right is evidence of an ancient period of heavy impact activity. The neutral gray color of Titania is characteristic of the Uranian satellites as a whole. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.26.1986
Umbriel at Closest Approach
Title Umbriel at Closest Approach
Description The southern hemisphere of Umbriel displays heavy cratering in this Voyager 2 image, taken Jan. 24, 1986, from a distance of 557,000 kilometers (346,000 miles). This frame, taken through the clear-filter of Voyager's narrow-angle camera, is the most detailed image of Umbriel, with a resolution of about 10 km (6 mi). Umbriel is the darkest of Uranus' larger moons and the one that appears to have experienced the lowest level of geological activity. It has a diameter of about 1,200 km (750 mi) and reflects only 16 percent of the light striking its surface, in the latter respect, Umbriel is similar to lunar highland areas. Umbriel is heavily cratered but lacks the numerous bright-ray craters seen on the other large Uranian satellites, this results in a relatively uniform surface albedo (reflectivity). The prominent crater on the terminator (upper right) is about 110 km (70 mi) across and has a bright central peak. The strangest feature in this image (at top) is a curious bright ring, the most reflective area seen on Umbriel. The ring is about 140 km (90 miles) in diameter and lies near the satellite's equator. The nature of the ring is not known, although it might be a frost deposit, perhaps associated with an impact crater. Spots against the black background are due to 'noise' in the data. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.27.1986
Uranus moon - Titania
Title Uranus moon - Titania
Description The terminator region of Titania, one of Uranus' five large moons, was captured in this Voyager 2 image obtained in the early morning hours of Jan. 24, 1986. Voyager was about 500,000 kilometers (300,000 miles) from Titania and inbound toward closest approach. This clear-filter, narrow-angle view is along the terminator -- the line between the sunlit and darkened parts of the moon. The low-angle illumination shows the shape of the surface very clearly. Among the features visible are long linear valleys perhaps 50-100 km (30-60 mi) wide and several hundred km (or mi) long. At least two directions of faulting are visible, as are many circular impact craters attributed to cosmic debris. The resolution of this image is about 9 km (6 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.25.1986
Uranus satellite - Miranda
Title Uranus satellite - Miranda
Description This Voyager 2 image of Miranda was taken Jan. 23, 1986, as the spacecraft neared Uranus. This image was acquired from a distance of 1.38 million kilometers (860,000 miles) through the clear filter of Voyager's narrow-angle camera. Miranda is the innermost of the five Uranian satellites known from Earth-based observations. Images from the Jan. 24 closest approach to Miranda should reveal in greater detail the region toward the bottom of this view, where a sinuous bright marking crosses a circular dark area. These features lie between a bright (high-albedo) region at left and a region of average albedo at right. Miranda is about 500 km (300 mi) in diameter, the resolution of this image is about 26 km (16 mi). The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.25.1986
Uranus' innermost satellite …
Title Uranus' innermost satellite Miranda
Description Miranda, innermost of Uranus' large satellites, is seen at close range in this Voyager 2 image, taken Jan. 24, 1986, as part of a high-resolution mosaicing sequence. Voyager was some 36,000 kilometers (22,000 miles) away from Miranda. This clear-filter, narrow-angle image shows an area about 250 km (150 mi) across, at a resolution of about 800 meters (2,600 feet). Two distinct terrain types are visible: a rugged, higher-elevation terrain (right) and a lower, striated terrain. Numerous craters on the rugged, higher terrain indicate that it is older than the lower terrain. Several scarps, probably faults, cut the different terrains. The impact crater in the lower part of this image is about 25 km (15 mi) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.26.1986
Uranus' rings
Title Uranus' rings
Description Voyager 2 took this wide-angle image of Uranus' rings as the spacecraft neared the plane of the rings less than an hour before closest approach to the planet. Voyager obtained this clear-filter image on Jan. 24, 1986, from a distance of about 117,000 kilometers (73,000 miles) from Uranus, resolution is about 16 km (10 mi). Running diagonally from upper left to lower center are the four sets of previously known discrete rings. Barely visible to the right of these appears the ansa of a very broad, faint ring not seen before. (The ansa is the portion of a ring visible on either side of a planet when viewed from a distance.) This inner ring extends about 3,000 km (1,900 mi) in width and is located approximately 1,500 km (900 mi) inside the innermost of the previously known discrete rings, the 6 ring. These figures place the inner edge of the newly found ring about 11,000 km (7,000 mi) above the cloud tops of Uranus. Since the ring is so faint, this image has been extensively processed, resulting in the blurry, patchy appearance. The diagram at right shows the positions of the inner ring and the four outer sets of rings. The Voyager project is managed for NASA by the Jet Propulsion Laboratory.
Date 01.28.1986
Dr. James C. Fletcher
Title Dr. James C. Fletcher
Full Description Dr. James C. Fletcher served as NASA Administrator from April 27, 1971, to May 1, 1977, and from May 12, 1986, to April 8, 1989. During his first administration at NASA, Dr. Fletcher was responsible for beginning the Shuttle effort, as well as the Viking program that sent landers to Mars. He oversaw the Skylab missions and Viking probes and approved the Voyager space probe, the Hubble Space Telescope and the Apollo-Soyuz Test Project. During his second tenure, he presided over the effort to recover from the Challenger accident. Dr. Fletcher died in December 1991 of lung cancer.
Date UNKNOWN
NASA Center Headquarters
Hubble Observes the Moons an …
Title Hubble Observes the Moons and Rings of the Planet Uranus
A86-7025
Photographer: JPL P-29509 BW …
1/26/86
Description Photographer: JPL P-29509 BW Range: 500,000 kilometers (300,000 miles) This high-resolution image of Titania was made as Voyager 2 neared its closest approach to Uranus. Voyager's narrow-angle camera acquired this image through the violet and clear filters and shows details about 9 km (6 mi) in size. Titania has a diameter of about 1,600 km (1,000 MI). In addition to many scars due to impacts, Titania displays evidence of other geologic activity at some point in its history. The large trench-like feature near the terminator (day-night boundary) at middle right suggests at least one episode of tectonic activity, Another, basinlike structure near the upper right is evidence of an ancient period of heavy impact activity. The neutral gray color of Titania is characteristic of the Uranian satellites as a whole.
Date 1/26/86
A86-7037
Photographer: JPL P-29521 BW …
1/24/86
Description Photographer: JPL P-29521 BW Range: 557,000 kilometers ( 346, 000 miles) The southern hemisphere of Umbriel displays heavy cratering in this Voyager 2 image. This frame, taken through the clear-filter of Voyager's narrow-angle camera, is the most detailed image of Umbriel, with a resolution of about 10 km (6 mi). Umbriel is the darkest of Uranus' larger moons and the one that appears to have experienced the lowest level of geological activity. It has a diameter of about 1,200 km (750 mi) and reflects only 16 percent of the light striking its surface, in the latter respect, Umbriel is similiar to lunar highland areas. Umbriel is heavily cratered but lacks the numerous bright-ray craters seen on the other large Uranian satellites, this results in a relatively uniform surface albedo (reflectivity). The prominent crater on the terminator (upper right) is about 110 km (70 mi) across and has a bright central peak. The strangest feature in this image (at top) is a curious bright ring, the most reflective area seen on Umbriel. The ring is about 140 km (90 mi) in diameter and lies near the satellite's equator. The nature of the ring is not known, although it might be a frost deposit, perhaps associated with an impact crater. Spots against the black background are due to "noise" in the data.
Date 1/24/86
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