|
|
| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
This Voyager 2 photograph of Titan, taken August 23, 1981 from a range of 2.3 million kilometers (1.4 million miles), shows some detail in the cloud systems on this Saturnian moon. The southern hemisphere appears lighter in contrast, a well-defined band is seen near the equator, and a dark collar is evident at the north pole. All these bands are associated with cloud circulation in Titan's atmosphere. The extended haze, composed of submicron-size particles, is seen clearly around the satellite's limb. This image was composed from blue, green and violet frames. For a high resolution image, click here. |
|
Iapetus' New Year's Flyby
| Description |
Iapetus' New Year's Flyby |
| Full Description |
This map of the surface of Saturn's moon Iapetus (1,436 kilometers, or 892 miles across), generated from images taken by NASA's Voyager spacecraft, illustrates the imaging coverage planned during Cassini's flyby on Dec. 31, 2004. Cassini will glide past Iapetus at a distance of approximately 123,400 kilometers (76,700 miles) on New Year's Eve, at a speed of about 2 kilometers per second (4,474 miles per hour). Imaging coverage will be focused primarily on the dark terrain of Iapetus' leading hemisphere, in the area known as Cassini Regio. The spacecraft's namesake, Jean-Dominique Cassini, discovered Iapetus in 1672 and was only able to see the moon's bright trailing hemisphere. Colored lines on the map enclose regions that will be covered at different imaging scales as Cassini approaches Iapetus. Images from Cassini's flyby will be superior in resolution to those obtained by Voyager 2 in August 1981. Voyager 2 passed Iapetus at a distance of approximately 909,000 kilometers (564,800 miles) at closest approach, yielding a best resolution image of about 8 kilometers per pixel. The resolution of Cassini images from this flyby will be 1.5 kilometers per pixel and better. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . For additional images visit the Cassini imaging team homepage http://ciclops.org . *Credit*: NASA/JPL/Space Science Institute |
| Date |
December 30, 2004 |
|
The Other Side of Iapetus
| Description |
Cassini captures the first high-resolution glimpse of the bright trailing hemisphere of Saturn's moon Iapetus. |
| Full Description |
Cassini captures the first high-resolution glimpse of the bright trailing hemisphere of Saturn's moon Iapetus. This false-color mosaic shows the entire hemisphere of Iapetus (1,468 kilometers, or 912 miles across) visible from Cassini on the outbound leg of its encounter with the two-toned moon in Sept. 2007. The central longitude of the trailing hemisphere is 24 degrees to the left of the mosaic's center. Also shown here is the complicated transition region between the dark leading and bright trailing hemispheres. This region, visible along the right side of the image, was observed in many of the images acquired by Cassini near closest approach during the encounter. Revealed here for the first time in detail are the geologic structures that mark the trailing hemisphere. The region appears heavily cratered, particularly in the north and south polar regions. Near the top of the mosaic, numerous impact features visible in NASA Voyager 2 spacecraft images (acquired in 1981) are visible, including the craters Ogier and Charlemagne. The most prominent topographic feature in this view, in the bottom half of the mosaic, is a 450-kilometer (280-mile) wide impact basin, one of at least nine such large basins on Iapetus. In fact, the basin overlaps an older, similar-sized impact basin to its southeast. In many places, the dark material -- thought to be composed of nitrogen-bearing organic compounds called cyanides, hydrated minerals and other carbonaceous minerals -- appears to coat equator-facing slopes and crater floors. The distribution of this material and variations in the color of the bright material across the trailing hemisphere will be crucial clues to understanding the origin of Iapetus' peculiar bright-dark dual personality. The view was acquired with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at a distance of about 73,000 kilometers (45,000 miles) from Iapetus. The color seen in this view represents an expansion of the wavelengths of the electromagnetic spectrum visible to human eyes. The intense reddish-brown hue of the dark material is far less pronounced in true color images. The use of enhanced color makes the reddish character of the dark material more visible than it would be to the naked eye. This mosaic consists of 60 images covering 15 footprints across the surface of Iapetus. The view is an orthographic projection centered on 10.8 degrees south latitude, 246.5 degrees west longitude and has a resolution of 426 meters (0.26 miles) per pixel. An orthographic view is most like the view seen by a distant observer looking through a telescope. At each footprint, a full resolution clear filter image was combined with half-resolution images taken with infrared, green and ultraviolet spectral filters (centered at 752, 568 and 338 nanometers, respectively) to create this full-resolution false color mosaic. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the, Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL/Space Science Institute |
| Date |
October 8, 2007 |
|
| Description |
Shepherd Satellites |
| Full Description |
This image taken by the Voyager 2 spacecraft of Saturn's A-ring shows the thin F-ring bracketed by its two shepherding satellites. Because the inner moon revolves around the planet slightly faster than the outer one, the satellites lap each other every 25 days. This picture was taken on August 15, 1981, when Voyager 2 was 10.5 million kilometers (6.6 million miles) from Saturn. At that instant, the shepherds were less than 1,800 kilometers (1,100 miles) apart. For higher resolution, click here. |
|
| Description |
Shepherd Satellites |
| Full Description |
This image taken by the Voyager 2 spacecraft of Saturn's A-ring shows the thin F-ring bracketed by its two shepherding satellites. Because the inner moon revolves around the planet slightly faster than the outer one, the satellites lap each other every 25 days. This picture was taken on August 15, 1981, when Voyager 2 was 10.5 million kilometers (6.6 million miles) from Saturn. At that instant, the shepherds were less than 1,800 kilometers (1,100 miles) apart. For higher resolution, click here. |
|
| Description |
Shepherd Satellites |
| Full Description |
This image taken by the Voyager 2 spacecraft of Saturn's A-ring shows the thin F-ring bracketed by its two shepherding satellites. Because the inner moon revolves around the planet slightly faster than the outer one, the satellites lap each other every 25 days. This picture was taken on August 15, 1981, when Voyager 2 was 10.5 million kilometers (6.6 million miles) from Saturn. At that instant, the shepherds were less than 1,800 kilometers (1,100 miles) apart. For higher resolution, click here. |
|
| Description |
Shepherd Satellites |
| Full Description |
This image taken by the Voyager 2 spacecraft of Saturn's A-ring shows the thin F-ring bracketed by its two shepherding satellites. Because the inner moon revolves around the planet slightly faster than the outer one, the satellites lap each other every 25 days. This picture was taken on August 15, 1981, when Voyager 2 was 10.5 million kilometers (6.6 million miles) from Saturn. At that instant, the shepherds were less than 1,800 kilometers (1,100 miles) apart. For higher resolution, click here. |
|
| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
This image taken by the Voyager 2 spacecraft of Saturn's A-ring shows the thin F-ring bracketed by its two shepherding satellites. Because the inner moon revolves around the planet slightly faster than the outer one, the satellites lap each other every 25 days. This picture was taken August 15, 1981, when Voyager 2 was 10.5 million kilometers (6.6 million miles) from Saturn. At that instant, the shepherds were less than 1,800 km. (1,100 mi.) apart, they passed each other about two hours later. (P-23911) |
|
Phoebe Looms in View
| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
Phoebe, Saturn's largest outer moon, is the first target of exploration for the Saturn-bound Cassini spacecraft. This composite shows a set of four images taken from June 7 through June 10, 2004, by the spacecraft as it approached Phoebe. This eccentric moon has a diameter of 220 kilometers (about 136.7 miles) and orbits Saturn in the opposite direction of its larger interior moons. Previous ground-based observations have shown water ice present on its surface. In 1981, Voyager 2 captured images of Phoebe from about 2.2 million kilometers (about 1.4 million miles) away. Cassini will obtain images from a mere 2,000 kilometers (about 1,240 miles) above the moon's surface. The closest approach to Phoebe will be at 1:56 p.m. Pacific Time on June 11, just 19 days before Saturn arrival. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org . Image Credit: NASA/JPL |
|
Phoebe Looms in View
| Description |
Here on the Gallery page you can find the very latest images, videos and products from the Cassini-Huygens mission to Saturn, including the spectacular launch, spacecraft assembly and the exciting trip to Saturn. |
| Full Description |
Phoebe, Saturn's largest outer moon, is the first target of exploration for the Saturn-bound Cassini spacecraft. This composite shows a set of four images taken from June 7 through June 10, 2004, by the spacecraft as it approached Phoebe. This eccentric moon has a diameter of 220 kilometers (about 136.7 miles) and orbits Saturn in the opposite direction of its larger interior moons. Previous ground-based observations have shown water ice present on its surface. In 1981, Voyager 2 captured images of Phoebe from about 2.2 million kilometers (about 1.4 million miles) away. Cassini will obtain images from a mere 2,000 kilometers (about 1,240 miles) above the moon's surface. The closest approach to Phoebe will be at 1:56 p.m. Pacific Time on June 11, just 19 days before Saturn arrival. For more information about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org . Image Credit: NASA/JPL |
|
The Other Side of Iapetus
| title |
The Other Side of Iapetus |
| date |
09.10.2007 |
| description |
Cassini captures the first high-resolution glimpse of the bright trailing hemisphere of Saturn's moon Iapetus. This false-color mosaic shows the entire hemisphere of Iapetus (1,468 kilometers, or 912 miles across) visible from Cassini on the outbound leg of its encounter with the two-toned moon in Sept. 2007. The central longitude of the trailing hemisphere is 24 degrees to the left of the mosaic's center. Also shown here is the complicated transition region between the dark leading and bright trailing hemispheres. This region, visible along the right side of the image, was observed in many of the images acquired by Cassini near closest approach during the encounter. Revealed here for the first time in detail are the geologic structures that mark the trailing hemisphere. The region appears heavily cratered, particularly in the north and south polar regions. Near the top of the mosaic, numerous impact features visible in NASA Voyager 2 spacecraft images (acquired in 1981) are visible, including the craters Ogier and Charlemagne. The most prominent topographic feature in this view, in the bottom half of the mosaic, is a 450-kilometer (280-mile) wide impact basin, one of at least nine such large basins on Iapetus. In fact, the basin overlaps an older, similar-sized impact basin to its southeast. In many places, the dark material -- thought to be composed of nitrogen-bearing organic compounds called cyanides, hydrated minerals and other carbonaceous minerals -- appears to coat equator-facing slopes and crater floors. The distribution of this material and variations in the color of the bright material across the trailing hemisphere will be crucial clues to understanding the origin of Iapetus' peculiar bright-dark dual personality. The view was acquired with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at a distance of about 73,000 kilometers (45,000 miles) from Iapetus. The color seen in this view represents an expansion of the wavelengths of the electromagnetic spectrum visible to human eyes. The intense reddish-brown hue of the dark material is far less pronounced in true color images. The use of enhanced color makes the reddish character of the dark material more visible than it would be to the naked eye. This mosaic consists of 60 images covering 15 footprints across the surface of Iapetus. The view is an orthographic projection centered on 10.8 degrees south latitude, 246.5 degrees west longitude and has a resolution of 426 meters (0.26 miles) per pixel. An orthographic view is most like the view seen by a distant observer looking through a telescope. At each footprint, a full resolution clear filter image was combined with half-resolution images taken with infrared, green and ultraviolet spectral filters (centered at 752, 568 and 338 nanometers, respectively) to create this full-resolution false color mosaic. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the, Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov ] . The Cassini imaging team homepage is at http://ciclops.org [ http://ciclops.org ] . Credit: NASA/JPL/Space Science Institute |
|
Iapetus
| title |
Iapetus |
| date |
08.22.1981 |
| description |
Saturn's outermost large moon, Iapetus, has a bright, heavily cratered icy terrain and a dark terrain, as shown in this Voyager 2 image taken on August 22, 1981. Amazingly, the dark material covers precisely the side of Iapetus that leads in the direction of orbital motion around Saturn (except for the poles), whereas the bright material occurs on the trailing hemisphere and at the poles. The bright terrain is made of dirty ice, and the dark terrain is surfaced by carbonaceous molecules, according to measurements made with Earth-based telescopes. Iapetus' dark hemisphere has been likened to tar or asphalt and is so dark that no details within this terrain were visible to Voyager 2. The bright icy hemisphere, likened to dirty snow, shows many large impact craters. The closest approach by Voyager 2 to Iapetus was a relatively distant 600,000 miles, so that our best images, such as this, have a resolution of about 12 miles. The dark material is made of organic substances, probably including poisonous cyano compounds such as frozen hydrogen cyanide polymers. Though we know a little about the dark terrain's chemical nature, we do not understand its origin. Two theories have been developed, but neither is fully satisfactory: (1) the dark material may be organic dust knocked off the small neighboring satellite Phoebe and "painted" onto the leading side of Iapetus as the dust spirals toward Saturn and Iapetus hurtles through the tenuous dust cloud, or (2) the dark material may be made of icy-cold carbonaceous "cryovolcanic" lavas that were erupted from Iapetus' interior and then blackened by solar radiation, charged particles, and cosmic rays. A determination of the actual cause, as well as discovery of any other geologic features smaller than 12 miles across, awaits the Cassini orbiter. *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 |
|
Stereo Saturn
| Title |
Stereo Saturn |
| Explanation |
Get out your red/blue glasses [ http://img.arc.nasa.gov/archive/desert96/redblue.html ] and launch [ http://antwrp.gsfc.nasa.gov/apod/ap971016.html ] yourself into this stereo [ http://cass.jsc.nasa.gov/research/stereo_atlas/SS3D.HTM ] picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2 spacecraft [ http://vraptor.jpl.nasa.gov/voyager/voyager_fs.html ] during its visit to [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] the Saturnian System in August of 1981. Traveling at about 35,000 miles per hour, the spacecraft's changing viewpoint from one image to the next produced this exaggerated but pleasing stereo effect [ http://antwrp.gsfc.nasa.gov/apod/ap970404.html ]. Saturn is the second largest planet [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/saturn.html ] in the Solar System, after Jupiter. Its spectacular ring system [ http://ringmaster.arc.nasa.gov/saturn/saturn.html ] is so wide that it would span the space between the Earth and Moon. Although they look solid here, Saturn's [ http://antwrp.gsfc.nasa.gov/apod/ap000129.html ] rings consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders. |
|
Dione's Lagrange Moon Helene
| Title |
Dione's Lagrange Moon Helene |
| Explanation |
Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap950705.html ]'s moon Helene [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/helene.html ] is very unusual in that it circles Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap950801.html ] near the orbit of a bigger moon: Dione [ http://antwrp.gsfc.nasa.gov/apod/ap951009.html ]. Helene is situated in what is called a "Lagrange point" of Dione - a place of stability created by Dione's gravity. Were Helene [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/dione.html#helene ] to stray slightly from its orbit 1/6 ahead of Dione, the larger moon's gravity would cause Helene to move back toward the Lagrange point. Many massive orbital bodies have stable Lagrange points, including the Earth and Moon. Helene was discovered from the ground by P. Laques & J. Lecacheux in 1980. The photograph above was taken by Voyager 2 as it passed Saturn in 1981. NASA's Cassini [ http://newproducts.jpl.nasa.gov/calendar/cassini.html ] mission to Saturn is currently scheduled for launch in October 1997. |
|
Saturn's Moon Tethys
| Title |
Saturn's Moon Tethys |
| Explanation |
Tethys is one of the larger and closer moons of Saturn. It was visited by both Voyager spacecraft [ http://voyager.jpl.nasa.gov/ ] - Voyager 1 in November 1980 and by Voyager [ http://antwrp.gsfc.nasa.gov/apod/ap960629.html ] 2 in August 1981. Tethys [ http://www.nineplanets.org/tethys.html ] is now known to be composed almost completely of water ice. Tethys [ http://www.solarviews.com/eng/tethys.htm ] shows a large impact crater [ http://antwrp.gsfc.nasa.gov/apod/ap990711.html ] that nearly circles the planet. That the impact that caused this crater did not disrupt the moon is taken as evidence that Tethys [ http://sse.jpl.nasa.gov/features/planets/saturn/tethys.html ] was not completely frozen in its past. Two smaller moons, Telesto [ http://www.nineplanets.org/tethys.html#telesto ] and Calypso [ http://www.nineplanets.org/tethys.html#calypso ], orbit Saturn [ http://antwrp.gsfc.nasa.gov/apod/saturn.html ] just ahead of and behind Tethys. Giovanni Cassini [ http://www-groups.dcs.st-and.ac.uk/~history/Mathematicians/Cassini.html ] discovered Tethys in 1684. In 1997, NASA [ http://www.nasa.gov/ ] launched [ http://antwrp.gsfc.nasa.gov/apod/ap971016.html ] a spacecraft named Cassini [ http://saturn.jpl.nasa.gov/cassini/english/spacecraft/ ] to Saturn that will arrive in 2004. |
|
Saturn's Moon Tethys
| Title |
Saturn's Moon Tethys |
| Explanation |
Tethys [ http://www.c3.lanl.gov/~cjhamil/SolarSystem/tethys.html ] is one of the larger and closer moons of Saturn [ http://antwrp.gsfc.nasa.gov/apod/ap951018.html ]. It was visited by both Voyager spacecraft - Voyager 1 in November 1980 and by Voyager 2 in August 1981. Tethys [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/tethys.html ] is now known to be composed almost completely of water ice. Tethys shows a large impact crater that nearly circles the planet. That the impact that caused this crater did not disrupt the moon is taken as evidence that Tethys was not completely frozen in its past. Tethys has two moons named Telesto [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/tethys.html#telesto ] and Calypso [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/tethys.html#calypso ] that orbit just ahead of it and behind it. Tethys was originally discovered in 1684 by Giovanni Cassini. |
|
Stereo Saturn
| Title |
Stereo Saturn |
| Explanation |
Get out your red/blue glasses [ http://mpfwww.jpl.nasa.gov/MPF/mpf/glasses.html ] and launch [ http://beacon.jpl.nasa.gov/exhibits/voyager/ default.html ] yourself into this stereo [ http://cass.jsc.nasa.gov/research/stereo_atlas/ SS3D.HTM ] picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2 spacecraft [ http://nssdc.gsfc.nasa.gov/database/ MasterCatalog?sc=1977-076A ] during its visit to [ http://sse.jpl.nasa.gov/missions/sat_missns/ sat-voy2.html ] the Saturnian System in August of 1981. Traveling at about 35,000 miles per hour, the spacecraft's changing viewpoint from one image to the next produced this exaggerated but pleasing stereo effect [ http://antwrp.gsfc.nasa.gov/apod/ap970404.html ]. Saturn is the second largest planet [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/ saturn.html ] in the Solar System, after Jupiter. Its spectacular ring system [ http://ringmaster.arc.nasa.gov/saturn/saturn.html ] is so wide that it would span the space between the Earth and Moon. Although they look solid here, Saturn's [ http://antwrp.gsfc.nasa.gov/apod/ap000129.html ] rings consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders. |
|
Stereo Saturn
| Title |
Stereo Saturn |
| Explanation |
Get out your red/blue glasses [ http://img.arc.nasa.gov/archive/desert96/redblue.html ] and launch [ http://antwrp.gsfc.nasa.gov/apod/ap981224.html ] yourself into this stereo [ http://cass.jsc.nasa.gov/research/stereo_atlas/SS3D.HTM ] picture of Saturn! The picture is actually composed from two images recorded weeks apart by the Voyager 2 spacecraft [ http://vraptor.jpl.nasa.gov/voyager/voyager_fs.html ] during its visit to the Saturnian System [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] in August of 1981. Traveling at about 35,000 miles per hour, the spacecraft's changing viewpoint from one image to the next produced this exaggerated but pleasing stereo effect [ http://antwrp.gsfc.nasa.gov/apod/ap970404.html ]. Saturn is the second largest planet in the Solar System [ http://seds.lpl.arizona.edu/nineplanets/nineplanets/saturn.html ], after Jupiter. Its spectacular ring system [ http://ringmaster.arc.nasa.gov/saturn/saturn.html ] is so wide that it would span the space between the Earth and Moon. Although they look solid here, Saturn's Rings [ http://antwrp.gsfc.nasa.gov/apod/ap981105.html ] consist of individually orbiting bits of ice and rock ranging in size from grains of sand to barn-sized boulders. |
|
Pictures of Tethys' large cr
| Title |
Pictures of Tethys' large crater. |
| Description |
This series of Voyager 2 pictures of Tethys shows its distinctive large crater, 400 kilometers (250 miles) in diameter, as it rotates toward the termination and limb of this satellite of Saturn. These images were obtained at four-hour intervals beginning late Aug. 24 and ending early the next day, the distances were 1.1 million km. (670,000 mi.), 826,000 km. (510,000 mi.) and 680,000 km. (420,000 mi.), respectively. The crater, the remnant of a large impact, has a central peak and several concentric rings. Some grooves radiating from the center may be formed of material thrown from the crater during the impact. The bottom frame, with the crater in profile, reveals that its floor has risen back to the spherical shape of the satellite, unlike the large crater seen on Tethys sister moon Mimas. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.26.1981 |
|
Rhea - icy cratered surface
| Title |
Rhea - icy cratered surface |
| Description |
The icy, cratered surface of Saturn's moon Rhea is seen in this image taken by Voyager 1 on Nov. 12, 1980, at a range of 85,000 kilometers (52,800 miles) as the spacecraft passed over the satellite's north pole. The heavily cratered surface attests to the satellite's ancient age. The largest craters, 50 to 100 kilometers (30 to 60 miles) across and several kilometers deep, are freshly preserved in Rhea's icy crust. The craters and landscape resemble those on the Moon and Mercury, and are unlike the flattened crater forms that have collapsed in the soft icy crusts of the Jovian moons Callisto, Ganymede and Europa. Scientists believe that Rhea (which is just 1,600 kilometers or 995 miles in diameter, compared to the 5,500-kilometer or 3,400-mile diameter of Ganymede) froze and became rigid, behaving like a rocky surface, very early in its history. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
02.10.1981 |
|
Saturn - high-resolution fil
| Title |
Saturn - high-resolution filtered image of Enceladus |
| Description |
This high-resolution filtered image of Enceladus was made from several images obtained Aug. 25 by Voyager 2 from a range of 119,000 kilometers (74,000 miles). It shows further surface detail on this Saturnian moon (also viewed in the accompanying release P-23955C/BW, S-2-50, imaged about the same time). Enceladus is seen to resemble Jupiter's Galilean satellite Ganymede, which is, however, about 10 times larger. Faintly visible here in "Saturnshine" is the hemisphere turned away from the sun. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.28.1981 |
|
Saturn - large crater on Tet
| Title |
Saturn - large crater on Tethys |
| Description |
Special processing has brought out surface detail in this Voyager 2 image focusing on the large crater on Tethys. The spacecraft took this photograph Aug. 25, when it was 826,000 kilometers (513,000 miles) from the icy moon of Saturn. Here, resolution is about 15 km. (9 mi.). The crater has been flattened by the flow of softer ice and no longer shows the deep bowl shape characteristic of fresh craters in hard, cold ice or rock. It appears to have been formed early in Tethys' history, at a time when its interior was still relatively warm and soft. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.30.1981 |
|
Saturn's moon Tethys
| Title |
Saturn's moon Tethys |
| Description |
Voyager 2 obtained this view of Saturn's moon Tethys on Aug.25 from a distance of 540,000 kilometers (335,000 miles). It shows the numerous impact craters and fault valleys of a very ancient surface. Tethys itself is 1,090 km. (675 mi.) in diameter, and the great chasm seen at the top of this image extends 1,700 km. (1,050 mi.), halfway across the satellite. The largest impact crater visible here is 90 km. (55 mi.) in diameter. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.26.1981 |
|
Surface of Enceladus
| Title |
Surface of Enceladus |
| Description |
The surface of Enceladus is seen in this closeup view obtained Aug. 25, when Voyager 2 was 112,000 kilometers (69,500 miles) from this satellite of Saturn. This view, in which Enceladus north pole is toward the bottom right, shows the moon to bear a striking resemblance of Ganymede, the largest Galilean satellite of Jupiter. Moderately cratered areas have been transected by strips of younger grooved terrain. This more recently formed terrain--the light cratering says it must be relatively young--has consumed portions of craters such as those near the bottom center of this picture. This suggests that Enceladus has experienced internal melting even though it is only about 490 km. (300 mi.) in diameter. The grooves and linear features indicate that the satellite has been subjected to considerable crustal deformation as a result of this internal melting. The largest crater visible here is about 35 km. (20 mi.) across. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.26.1981 |
|
Tethys
| Title |
Tethys |
| Description |
The Saturn satellite Tethys was viewed by Voyager 2 on Aug. 25 from a distance of 1 million kilometers (620,000 mi.). Evident on the surface of this icy moon is an enormous impact crater almost 400 km. (250 mi.) in diameter and about 15 km. (10 mi.) deep. Tethys itself is only 1,050 km. (650 mi.) in diameter. The crater contains a central peak about as high as the crater is deep, it is the result of rebound after the impact. Tethys resembles its sister satellite Mimas, seen closeup by Voyager 1 last fall. That body has a crater 130 km. (80 mi.) in diameter. The Tethys crater, which is so large that Mimas would fit inside, is on the opposite side of the great rift valley observed by Voyager 1. Many other, smaller craters pock-mark the surface here. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.25.1981 |
|
Iapetus Bright and Dark Terr
| Title |
Iapetus Bright and Dark Terrains |
| Description |
Saturn's outermost large moon, Iapetus, has a bright, heavily cratered icy terrain and a dark terrain, as shown in this Voyager 2 image taken on August 22, 1981. Amazingly, the dark material covers precisely the side of Iapetus that leads in the direction of orbital motion around Saturn (except for the poles), whereas the bright material occurs on the trailing hemisphere and at the poles. The bright terrain is made of dirty ice, and the dark terrain is surfaced by carbonaceous molecules, according to measurements made with Earth-based telescopes. Iapetus' dark hemisphere has been likened to tar or asphalt and is so dark that no details within this terrain were visible to Voyager 2. The bright icy hemisphere, likened to dirty snow, shows many large impact craters. The closest approach by Voyager 2 to Iapetus was a relatively distant 600,000 miles, so that our best images, such as this, have a resolution of about 12 miles. The dark material is made of organic substances, probably including poisonous cyano compounds such as frozen hydrogen cyanide polymers. Though we know a little about the dark terrain's chemical nature, we do not understand its origin. Two theories have been developed, but neither is fully satisfactory--(1) the dark material may be organic dust knocked off the small neighboring satellite Phoebe and "painted" onto the leading side of Iapetus as the dust spirals toward Saturn and Iapetus hurtles through the tenuous dust cloud, or (2) the dark material may be made of icy-cold carbonaceous "cryovolcanic" lavas that were erupted from Iapetus' interior and then blackened by solar radiation, charged particles, and cosmic rays. A determination of the actual cause, as well as discovery of any other geologic features smaller than 12 miles across, awaits the Cassini Saturn orbiter to arrive in 2004. |
| Date |
04.01.1990 |
|
Iapetus' New Year's Flyby
PIA06165
Saturn
Imaging Science Subsystem -
| Title |
Iapetus' New Year's Flyby |
| Original Caption Released with Image |
Figure 1 This map of the surface of Saturn's moon Iapetus (1,436 kilometers, or 892 miles across), generated from images taken by NASA's Voyager spacecraft, illustrates the imaging coverage planned during Cassini's flyby on Dec. 31, 2004. Cassini will glide past Iapetus at a distance of approximately 123,400 kilometers (76,700 miles) on New Year's Eve, at a speed of about 2 kilometers per second (4,474 miles per hour). Imaging coverage will be focused primarily on the dark terrain of Iapetus' leading hemisphere, in the area known as Cassini Regio. The spacecraft's namesake, Jean-Dominique Cassini, discovered Iapetus in 1672 and was only able to see the moon's bright trailing hemisphere. In figure 1, colored lines on the map enclose regions that will be covered at different imaging scales as Cassini approaches Iapetus. Images from Cassini's flyby will be superior in resolution to those obtained by Voyager 2 in August 1981. Voyager 2 passed Iapetus at a distance of approximately 909,000 kilometers (564,800 miles) at closest approach, yielding a best resolution image of about 8 kilometers per pixel. The resolution of Cassini images from this flyby will be 1.5 kilometers per pixel and better. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov ]. For additional images visit the Cassini imaging team homepage http://ciclops.org [ http://ciclops.org ]. |
|
Iapetus' New Year's Flyby
PIA06165
Saturn
Imaging Science Subsystem -
| Title |
Iapetus' New Year's Flyby |
| Original Caption Released with Image |
Figure 1 This map of the surface of Saturn's moon Iapetus (1,436 kilometers, or 892 miles across), generated from images taken by NASA's Voyager spacecraft, illustrates the imaging coverage planned during Cassini's flyby on Dec. 31, 2004. Cassini will glide past Iapetus at a distance of approximately 123,400 kilometers (76,700 miles) on New Year's Eve, at a speed of about 2 kilometers per second (4,474 miles per hour). Imaging coverage will be focused primarily on the dark terrain of Iapetus' leading hemisphere, in the area known as Cassini Regio. The spacecraft's namesake, Jean-Dominique Cassini, discovered Iapetus in 1672 and was only able to see the moon's bright trailing hemisphere. In figure 1, colored lines on the map enclose regions that will be covered at different imaging scales as Cassini approaches Iapetus. Images from Cassini's flyby will be superior in resolution to those obtained by Voyager 2 in August 1981. Voyager 2 passed Iapetus at a distance of approximately 909,000 kilometers (564,800 miles) at closest approach, yielding a best resolution image of about 8 kilometers per pixel. The resolution of Cassini images from this flyby will be 1.5 kilometers per pixel and better. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov ]. For additional images visit the Cassini imaging team homepage http://ciclops.org [ http://ciclops.org ]. |
|
Iapetus Bright and Dark Terr
PIA00348
Saturn
Imaging Science Subsystem -
| Title |
Iapetus Bright and Dark Terrains |
| Original Caption Released with Image |
Saturn's outermost large moon, Iapetus, has a bright, heavily cratered icy terrain and a dark terrain, as shown in this Voyager 2 image taken on August 22, 1981. Amazingly, the dark material covers precisely the side of Iapetus that leads in the direction of orbital motion around Saturn (except for the poles), whereas the bright material occurs on the trailing hemisphere and at the poles. The bright terrain is made of dirty ice, and the dark terrain is surfaced by carbonaceous molecules, according to measurements made with Earth-based telescopes. Iapetus' dark hemisphere has been likened to tar or asphalt and is so dark that no details within this terrain were visible to Voyager 2. The bright icy hemisphere, likened to dirty snow, shows many large impact craters. The closest approach by Voyager 2 to Iapetus was a relatively distant 600,000 miles, so that our best images, such as this, have a resolution of about 12 miles. The dark material is made of organic substances, probably including poisonous cyano compounds such as frozen hydrogen cyanide polymers. Though we know a little about the dark terrain's chemical nature, we do not understand its origin. Two theories have been developed, but neither is fully satisfactory--(1) the dark material may be organic dust knocked off the small neighboring satellite Phoebe and "painted" onto the leading side of Iapetus as the dust spirals toward Saturn and Iapetus hurtles through the tenuous dust cloud, or (2) the dark material may be made of icy-cold carbonaceous "cryovolcanic" lavas that were erupted from Iapetus' interior and then blackened by solar radiation, charged particles, and cosmic rays. A determination of the actual cause, as well as discovery of any other geologic features smaller than 12 miles across, awaits the Cassini Saturn orbiter to arrive in 2004. |
|
The Other Side of Iapetus
PIA08384
Saturn
Imaging Science Subsystem -
| Title |
The Other Side of Iapetus |
| Original Caption Released with Image |
Cassini captures the first high-resolution glimpse of the bright trailing hemisphere of Saturn's moon Iapetus. This false-color mosaic shows the entire hemisphere of Iapetus (1,468 kilometers, or 912 miles across) visible from Cassini on the outbound leg of its encounter with the two-toned moon in Sept. 2007. The central longitude of the trailing hemisphere is 24 degrees to the left of the mosaic's center. Also shown here is the complicated transition region between the dark leading and bright trailing hemispheres. This region, visible along the right side of the image, was observed in many of the images acquired by Cassini near closest approach during the encounter. Revealed here for the first time in detail are the geologic structures that mark the trailing hemisphere. The region appears heavily cratered, particularly in the north and south polar regions. Near the top of the mosaic, numerous impact features visible in NASA Voyager 2 spacecraft images (acquired in 1981) are visible, including the craters Ogier and Charlemagne. The most prominent topographic feature in this view, in the bottom half of the mosaic, is a 450-kilometer (280-mile) wide impact basin, one of at least nine such large basins on Iapetus. In fact, the basin overlaps an older, similar-sized impact basin to its southeast. In many places, the dark material--thought to be composed of nitrogen-bearing organic compounds called cyanides, hydrated minerals and other carbonaceous minerals--appears to coat equator-facing slopes and crater floors. The distribution of this material and variations in the color of the bright material across the trailing hemisphere will be crucial clues to understanding the origin of Iapetus' peculiar bright-dark dual personality. The view was acquired with the Cassini spacecraft narrow-angle camera on Sept. 10, 2007, at a distance of about 73,000 kilometers (45,000 miles) from Iapetus. The color seen in this view represents an expansion of the wavelengths of the electromagnetic spectrum visible to human eyes. The intense reddish-brown hue of the dark material is far less pronounced in true color images. The use of enhanced color makes the reddish character of the dark material more visible than it would be to the naked eye. This mosaic consists of 60 images covering 15 footprints across the surface of Iapetus. The view is an orthographic projection centered on 10.8 degrees south latitude, 246.5 degrees west longitude and has a resolution of 426 meters (0.26 miles) per pixel. An orthographic view is most like the view seen by a distant observer looking through a telescope. At each footprint, a full resolution clear filter image was combined with half-resolution images taken with infrared, green and ultraviolet spectral filters (centered at 752, 568 and 338 nanometers, respectively) to create this full-resolution false color mosaic. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian, Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm [ http://saturn.jpl.nasa.gov ]. The Cassini imaging team homepage is at http://ciclops.org [ http://ciclops.org ]. |
|
Closing in on Phoebe
PIA06062
Saturn
Imaging Science Subsystem -
| Title |
Closing in on Phoebe |
| Original Caption Released with Image |
The Cassini spacecraft is closing in fast on its first target of observation in the Saturn system: the small, mysterious moon Phoebe, only 220 kilometers (137 miles) across. The three images shown here, the latest of which is twice as good as any image returned by the Voyager 2 spacecraft in 1981, were captured in the past week on approach to this outer moon of Saturn. Phoebe's surface is already showing a great deal of contrast, most likely indicative of topography, such as tall sunlit peaks and deep shadowy craters, as well as genuine variation in the reflectivity of its surface materials. Left to right, the three views were captured at a phase (Sun-Saturn-spacecraft) angle of 87 degrees between June 4 and June 7, from distances ranging from 4.1 million kilometers (2.6 million miles) to 2.5 million kilometers (1.5 million miles). The image scale ranges from 25 to 15 kilometers per pixel. Phoebe rotates once every nine hours and 16 minutes, each of these images shows a different region on Phoebe. Phoebe was the discovered in 1898. It has a very dark surface. Cassini's powerful cameras will provide the best-ever look at this moon on Friday, June 11, when the spacecraft will streak past Phoebe at a distance of only about 2,000 kilometers (1,240 miles) from the moon's surface. The current images, and the presence of large craters, promise a heavily cratered surface which will come into sharp view over the next few days when image scales should get as small as a few tens of meters. Phoebe orbits Saturn in a direction opposite to that of the larger interior Saturnian moons. Because of its small size and retrograde orbit Phoebe is believed to be a body from the distant outer solar system, perhaps one of the building blocks of the outer planets that were captured into orbit around Saturn. If true, the little moon will provide information about these primitive pieces of material. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Office of Space Science, Washington, D.C. The Cassini orbiter and its two onboard cameras, were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information, about the Cassini-Huygens mission visit, http://saturn.jpl.nasa.gov [ http://saturn.jpl.nasa.gov/ ] and the Cassini imaging team home page, http://ciclops.org [ http://ciclops.org/ ]. |
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