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Voyager of Jet Propulsion Laboratory (JPL) from 1981
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S-2 BW-4
Prominent dark spokes are vi
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8/13/81
| Date |
8/13/81 |
| Description |
Prominent dark spokes are visible in the outer half of Saturn’s broad B-ring in this Voyager 2 photograph taken on Aug. 3, 1981 from a range of about 22 million kilometers (14 million miles). The features appear as filamentary markings about 12,000 kilometers (7,S00 miles) long, which rotate around the planet with the motion of particles in the rings. The nature of these features, discovered by Voyager 1, is not totally understood, but scientists believe the spokes may be caused by dust levitated above the ring plane by electric fields, Voyager 2 photography of the rings edge-on, scheduled for Aug. 25, 1981, will provide an opportunity to test that theory. Because the Sun is now illuminating the rings from a higher angle, Voyager 2’s photographs reveal ring structure from a greater distance than that seen by Voyager 1 in its November 1980 encounter. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
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| 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. |
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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 |
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Enceladus: Trailing Hemisphe
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| Description |
Enceladus: Trailing Hemisphere |
| Full Description |
A variety of surface ages is revealed in this 16-image mosaic taken during Cassini's first close flyby of Enceladus, on Feb. 17, 2005. This mosaic shows the trailing hemisphere of Enceladus -- the side of Enceladus that always faces away from the direction of the satellite's orbital motion. This hemisphere is dominated by Sarandib Planitia (just right of center), a region thought to be dominated by smooth plains in NASA Voyager 2 images taken in August 1981, but shown here in much higher resolution images to be covered in low ridges and troughs. Other major features seen in the region include Labtayt Sulci, a 1-kilometer- (0.6-mile-) deep canyon running northward from a cusp in the south polar terrain boundary (Cashmere Sulci) at lower right to a set of 1-kilometer-tall ridges (Cufa Dorsa and Ebony Dorsum) east of Sarandib Planitia (also seen in Enceladus Mosaic), as well as Samarkand Sulci, a band of ridges and troughs running along the western margin of Sarandib Planitia almost all the way north to Enceladus' north pole. In contrast to the youthful terrain of Sarandib Planitia and the terrain south of it, the terrain north and west of Sarandib appears much older. These regions are covered with impact craters at various stages of degradation, either from viscous relaxation (which causes the craters to flatten over time), or from tectonic activity. To create this single full-disk mosaic, the 16 images were reprojected into an orthographic projection centered at 2.3 degrees north latitude, 317.7 degrees west longitude with a pixel scale of 63 meters (207 feet) per pixel. The original images were taken by the Cassini spacecraft narrow-angle and wide-angle cameras from distances ranging from 10,850 to 29,750 kilometers (6,740 to 18,490 miles). The images had a phase, or sun-Enceladus-spacecraft, angle of 28 degrees. 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 |
December 29, 2006 |
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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 |
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On the Final Frontier
| Description |
Saturn sits nested in its rings of ice as Cassini once again plunges toward the graceful giant. |
| Full Description |
Saturn sits nested in its rings of ice as Cassini once again plunges toward the graceful giant. This natural color mosaic was acquired by the Cassini spacecraft as it soared 39 degrees above the unilluminated side of the rings. Little light makes its way through the rings to be scattered in Cassini's direction in this viewing geometry, making the rings appear somewhat dark compared to the reflective planet. The view can be contrasted with earlier mosaics designed to showcase the rings rather than the planet, which were therefore given longer exposure times (see Blinding Saturn and Ring World). Bright clouds play in the blue-gray skies of the north. The ring shadows continue to caress the planet as they slide farther south toward their momentary disappearance during equinox in 2009. The rings' reflected light illuminates the southern hemisphere on Saturn's night side. The scene is reminiscent of the parting glance of NASA's Voyager 1 as it said goodbye to Saturn in 1981 (see PIA00335). Cassini, however, will continue to orbit Saturn for many years to come. Three of Saturn's moons are visible in this image: Mimas (397 kilometers, or 247 miles across) at the 2 o'clock position, Janus (181 kilometers, or 113 miles across) at the 4 o'clock position and Pandora (84 kilometers, or 52 miles across) at the 8 o'clock position. Pandora is a faint speck just outside the narrow F ring. This mosaic was constructed from wide-angle camera images taken just before the narrow-angle camera mosaic PIA08389. The view combines 45 images -- 15 separate sets of red, green and blue images -- taken over the course of about two hours, as Cassini scanned across the entire main ring system. The images in this view were obtained on May 9, 2007, at a distance of approximately 1.1 million kilometers (700,000 miles) from Saturn. Image scale is about 62 kilometers (39 miles) per pixel. 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 15, 2007 |
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| 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. |
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| Description |
Ring Spokes |
| Full Description |
Voyager 2 obtained this high-resolution picture of Saturn's rings on August 22, 1981 when the spacecraft was 4 million km (2.5 million mi) away. Evident here are the numerous "spoke" features in the B ring, their sharp, narrow appearance suggests short formation times. Scientists think electromagnetic forces are responsible in some way for these features, but no detailed theory has been worked out. Spokes of this nature were observed to persist at times for two or three rotations of the ring about the planet. Freshly-formed spokes seemed to revolve around the planet at the same rate as the rotation of the magnetic field and the interior of Saturn, independent of their distance from the center of Saturn. It is therefore suspected that the tiny dust grains which form the spokes are electrically charged. Older spokes, which presumably have lost their electrical charge, revolve with the underlying larger ring particles. For a high resolution image, click here. |
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| 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 enhanced-color image was created by combining three images taken through ultraviolet, violet and green filters on July 12, 1981. Several changes were apparent in Saturn's atmosphere since Voyager 1's November 1980 encounter, and the planet's rings had brightened considerably due to the higher sun angle. Voyager 2 was 43 million kilometers (27 million miles) from Saturn when it took this photograph. (P-23880) |
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| Description |
Ring Spokes |
| Full Description |
Voyager 2 obtained this high-resolution picture of Saturn's rings on August 22, 1981 when the spacecraft was 4 million kilometers (2.5 million miles) away. Evident here are the numerous "spoke" features in the B ring, their sharp, narrow appearance suggests short formation times. Scientists think electromagnetic forces are responsible in some way for these features, but no detailed theory has been worked out. Spokes of this nature were observed to persist at times for two or three rotations of the ring about the planet. Freshly-formed spokes seemed to revolve around the planet at the same rate as the rotation of the magnetic field and the interior of Saturn, independent of their distance from the center of Saturn. It is therefore suspected that the tiny dust grains which form the spokes are electrically charged. Older spokes, which presumably have lost their electrical charge, revolve with the underlying larger ring particles. For a high resolution image, click here. |
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| Description |
Ring Color Variations |
| Full Description |
Possible variations in chemical composition from one part of Saturn's ring system to another are visible in this Voyager 2 picture as subtle color variations that can be recorded with special computer-processing techniques. This highly enhanced color view was assembled from clear, orange and ultraviolet frames obtained August 17, 1981 from a distance of 8.9 million kilometers (5.5 million miles). In addition to the previously known blue color of the C-ring and the Cassini Division, the picture shows additional color differences between the inner B-ring and outer region (where the spokes form) and between these and the A-ring. For a high resolution image, click here. |
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| 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. |
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| 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. |
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Video greeting to NASA JPL b
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| 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 |
Saturn. Why this change? Well, for one thing it made a more straightforward storyline. And more important, the special effects department couldn't produce a Saturn that Stanley found convincing. That was just as well because if they had done so, the movie would have been badly dated by the Voyager missions, which showed Saturn's rings to be far more implausible than anyone had ever imagined. I have seen enough instances where Nature imitates art, so I'm going to keep my fingers crossed on what Cassini discovers at Iapetus. I want to thank everyone associated with this mission and the overall project. It may lack the glamour of manned spaceflight, but science projects are tremendously important for our understanding of the Solar System. And who knows, one day our survival on Earth might depend on what we discover out there. This is Arthur Clarke, wishing you a successful flyby., Video greeting to NASA JPL to mark the Iapetus flyby of Cassini spacecraft -- Sept. 10, 2007 by Arthur C. Clarke (The following is a transcript of the video greeting.) Hello! This is Arthur Clarke, joining you from my home in Colombo, Sri Lanka. I'm delighted to be part of this event to mark Cassini's flyby of Iapetus. I send my greetings to all my friends - known and unknown - who are gathered for this important occasion. I only wish I could be with you, but I'm now completely wheelchaired by Polio and have no plans to leave Sri Lanka again. Thanks to the World Wide Web, I have been following the progress of Cassini-Huygens mission from the time it was launched several years ago. As you know, I have more than a passing interest in Saturn. And I was really spooked in early 2005, when the Huygens probe returned sound recordings from the surface of Titan. This is exactly what I had described in my 1975 novel Imperial Earth, where my character is listening to the winds blowing over the desert plains. Perhaps that was a foretaste of things to come! On September 10, if everything goes according to plan, Cassini would give us our closest look at Iapetus - one of Saturn's most interesting moons. Half of Iapetus appears as dark as asphalt, and the other half is as bright as snow. When Giovanni Cassini discovered Iapetus in 1671, he could only see the bright side. We had a better glimpse when Voyager 2 flew past in August 1981 - but that was from almost a million kilometers away. In contrast, Cassini is going to come within a little over one thousand kilometers of Iapetus. This is a particularly exciting moment for fans of 2001: A Space Odyssey - because that's where the lone astronaut Dave Bowman discovers the Saturn monolith, which turns out to be a gateway to the stars. Chapter 35 in the novel is titled 'The Eye of Iapetus', and it contains this passage: "Iapetus was approaching so slowly that it scarcely seemed to move, and it was impossible to tell the exact moment when it made the subtle change from an astronomical body to a landscape, only fifty miles below. The faithful verniers gave their last spurts of thrust, then closed down forever. The ship was in its final orbit, completing a revolution every three hours at a mere eight hundred miles an hour - all the speed that was necessary in this feeble gravitation field." More than 40 years later, I cannot remember why I placed the Saturn monolith on Iapetus. At that time, in the early days of the Space Age, earth-based telescopes couldn't show any details of this celestial body. But I have always had a strange fascination for Saturn and its family of Moons. By the way, that 'family' has been growing at a very impressive rate. When Cassini was launched, we knew of only 18 moons. I understand it is now 60 - and counting.I can't resist the temptation to say: My God, it's full of moons! But in the movie, Stanley Kubrick decided to place all the actions at Jupiter, not |
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| 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. |
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| 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) |
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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 |
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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 |
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| Description |
Hyperion |
| Full Description |
Voyager 2 obtained this closeup view of Saturn's satellite Hyperion on August 24, 1981, from a distance of about 500,000 kilometers (300,000 miles). This photograph was compiled from three separate images taken through violet, clear and green filters. It shows Hyperion to be an irregular, disc-shaped body. Its longest dimension is 360 km. (225 mi.), but in this view, it presents a face measuring 325 km. by 250 km. (200 mi. by 150 mi.). The irregular shape is probably a result of repeated impacts that have taken off large pieces of the satellite. The large indentation at the bottom limb is one such crater, it is about 100 km. (60 mi.) across. The numerous small pits are impact craters, the smallest measuring about 10-20 km. (6-12 mi.) across. (P-23936) |
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Watching Saturn's Winds
| Description |
Subtle features in Saturn's equatorial region and the nearly edge-on rings are captured in this view. |
| Full Description |
Subtle features in Saturn's equatorial region and the nearly edge-on rings are captured in this view. Images like this will be carefully studied to see if changes in wind speed recorded in Hubble Space Telescope images are continuing, or whether the winds have reverted to their high-speed configuration measured by Voyager in 1981. The image was taken with the Cassini spacecraft narrow-angle camera on Dec. 6, 2005 using a filter sensitive to wavelengths of infrared light centered at 727 nanometers and at a distance of approximately 3 million kilometers (1.9 million miles) from Saturn. The image scale is 35 kilometers (22 miles) per pixel. 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 |
January 9, 2006 |
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| 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 true color picture was assembled from Voyager 2 Saturn images obtained August 4, 1981 from a distance of 21 million kilometers (13 million miles) on the spacecraft's approach trajectory. Three of Saturn's icy moons are evident at left. They are, in order of distance from the planet: Tethys, 1,050 km. (652 mi.) in diameter, Dione, 1,120 km. (696 mi.), and Rhea, 1,530 km. (951 mi.). The shadow of Tethys appears on Saturn's southern hemisphere. A fourth satellite, Mimas, is less evident, appearing as a bright spot a quarter-inch in in from the planet's limb about half an inch above Tethys, the shadow of Mimas appears on the planet about three-quarters of an inch directly above that of Tethys. The pastel and yellow hues on the planet reveal many contrasting bright and darker bands in both hemispheres of Saturn's weather system. For a high resolution image, click here. |
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Saturn's C-Ring
| title |
Saturn's C-Ring |
| date |
08.03.1981 |
| description |
This Voyager 2 view, focusing on Saturn's C-ring (and to a lesser extent, the B-ring at top and left) was compiled from three separate images taken through ultraviolet, clear and green filters. When it acquired these frames, Voyager 2 was 2.7 million kilometers (1.7 million miles) from the planet. In general, C-ring material is very bland and gray, the color of dirty ice. Color differences between this ring and the B-ring indicate differing surface compositions for the material composing these complex structures. More than 60 bright and dark ringlets are evident here, the small, bland squares are caused by the removal of reseau (reference) marks during processing. *Image Credit*: NASA |
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Voyager 2 Launch
| title |
Voyager 2 Launch |
| date |
08.20.1977 |
| description |
Voyager 2 was launched August 20, 1977, sixteen days before Voyager 1 aboard a Titan-Centaur rocket. Their different flight trajectories caused Voyager 2 to arrive at Jupiter four months later than Voyager 1, thus explaining their numbering. The initial mission plan for Voyager 2 specified visits only to Jupiter and Saturn. The plan was augmented in 1981 to include a visit to Uranus, and again in 1985 to include a flyby of Neptune. After completing the tour of the outer planets in 1989, the Voyager spacecraft began exploring interstellar space. The Voyager mission has been managed by NASA's Office of Space Science and the Jet Propulsion Laboratory. *Image Credit*: NASA |
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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 |
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On the Final Frontier
| title |
On the Final Frontier |
| date |
05.09.2007 |
| description |
Saturn sits nested in its rings of ice as Cassini once again plunges toward the graceful giant. This natural color mosaic was acquired by the Cassini spacecraft as it soared 39 degrees above the unilluminated side of the rings. Little light makes its way through the rings to be scattered in Cassini's direction in this viewing geometry, making the rings appear somewhat dark compared to the reflective planet. The view can be contrasted with earlier mosaics designed to showcase the rings rather than the planet, which were therefore given longer exposure times (see Blinding Saturn [ http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=5463 ] and Ring World [ http://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=2508 ]). Bright clouds play in the blue-gray skies of the north. The ring shadows continue to caress the planet as they slide farther south toward their momentary disappearance during equinox in 2009. The rings' reflected light illuminates the southern hemisphere on Saturn's night side. The scene is reminiscent of the parting glance of NASA's Voyager 1 as it said goodbye to Saturn in 1981 (see Saturn's Shadow [ http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=2121 ]). Cassini, however, will continue to orbit Saturn for many years to come. Three of Saturn's moons are visible in this image: Mimas (397 kilometers, or 247 miles across) at the 2 o'clock position, Janus (181 kilometers, or 113 miles across) at the 4 o'clock position and Pandora (84 kilometers, or 52 miles across) at the 8 o'clock position. Pandora is a faint speck just outside the narrow F ring. This mosaic was constructed from wide-angle camera images taken just before the narrow-angle camera mosaic Expance of Ice. The view combines 45 images -- 15 separate sets of red, green and blue images -- taken over the course of about two hours, as Cassini scanned across the entire main ring system. The images in this view were obtained on May 9, 2007, at a distance of approximately 1.1 million kilometers (700,000 miles) from Saturn. Image scale is about 62 kilometers (39 miles) per pixel. 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 |
|
Voyager 2 Looks at Saturn's
…
| title |
Voyager 2 Looks at Saturn's Rings |
| date |
08.17.1981 |
| description |
Voyager 2 false-color image of Saturn's rings. Subtle color variations due to differences in surface composition of the particles making up the rings are enhanced in this image produced by combining ultraviolet, clear, and orange frames. The frame was taken from a distance of 8.9 million km on August 17, 9 days before closest approach, and measures about 68,000 km from top to bottom. (Voyager 2, P-23953) *Image Credit*: NASA |
|
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 |
|
Fuzzy Phoebe
| title |
Fuzzy Phoebe |
| date |
09.04.1981 |
| description |
Voyager 2 took this photo sequence of Saturn's outer satellite, Phoebe, on Sept. 4, 1981, from 2.2 million kilometers (1.36 million miles) away. The top image is the normal version and the bottom is an enhanced version to increase resolution. This sequence lasts 23.4 hours and contains 35 images. The early images were taken about 43 minutes apart, while the later ones are about 29 minutes apart. There are two significant gaps in the sequence: images 7 and 8 are separated by 2.3 hours and images 19 and 20 are separated by 2.8 hours. Because the sunlight is coming from the left, mountains and ridges can best be seen as they reflect the sunlight near the terminator (right side of Phoebe). Other intrinsically bright spots can be seen rotating across the whole disk. In this time-lapse sequence, Phoebe appears to be a lumpy spheroid with possible large mountains sometimes showing on the limb (left side of Phoebe). The photos show that Phoebe is about 220 kilometers (132 miles) in diameter. Its rotation period (length of day) was determined from this set of images to be 9.4 hours. The photo shows that Phoebe is about twice the size of Earth-based measurements, and dark, with five percent reflectivity -- much darker than any other Saturnian satellite. That, and information from Earth-based observations, indicates Phoebe is almost certainly a captured asteroid or Kuiper Belt object, and did not form in the original Saturn nebula as Saturn's other satellites did. Phoebe is the only Saturnian satellite that does not always show the same face to Saturn: Its orbital period is 550 days. Its rotation period (length of day), determined from Voyager 2 observations, is nine to ten hours. Other ground-based observations that indicate that Phoebe is a captured asteroid: It orbits Saturn in the ecliptic plane (the plane in which Earth and most other planets orbit the Sun), rather than in Saturn's equatorial plane as the other Saturn satellites do. And Phoebe's orbit is retrograde -- in the direction opposite to that of the other satellites. *Image Credit*: NASA |
|
Saturn's Rings
| Title |
Saturn's Rings |
| Full Description |
This Voyager 2 view, focusing on Saturn's C-ring (and to a lesser extent, the B- ring at top and left) was compiled from three separate images taken through ultraviolet, clear and green filters. On August 23, 1981, when it acquired these frames, Voyager 2 was 2.7 million kilometers (1.7 million miles) from the planet. In general, C-ring material is very bland and gray, the color of dirty ice. Color differences between this ring and the B-ring indicate differing surface compositions for the material composing these complex structures. More than 60 bright and dark ringlets are evident here, the small, bland squares are caused by the removal of reseau (reference) marks during processing. |
| Date |
08/25/1981 |
| NASA Center |
Jet Propulsion Laboratory |
|
Solar System Montage of Voya
…
| Title |
Solar System Montage of Voyager Images |
| Full Description |
This montage of images taken by the Voyager spacecraft of the planets and four of Jupiter's moons is set against a false-color Rosette Nebula with Earth's moon in the foreground. Studying and mapping Jupiter, Saturn, Uranus, Neptune, and many of their moons, Voyager provided scientists with better images and data than they had ever had before or expected from the program. Although launched sixteen days after Voyager 2, Voyager 1's trajectory was a faster path, arriving at Jupiter in March 1979. Voyager 2 arrived about four months later in July 1979. Both spacecraft were then directed to Saturn with Voyager 1 arriving in November 1980 and Voyager 2 in August 1981. Voyager 2 was then diverted to the remaining gas giants, Uranus in January 1986 and Neptune in August 1989. Data collection continues by both Voyager 1 and 2 as the renamed Voyager Interstellar Mission searches for the edge of the solar wind influence (the heliopause) and exits the Solar System. A shortened list of the discoveries of Voyager 1 and 2 include:the discovery of the Uranian and Neptunian magnetospheres (magnetic environments caused by various types of planet cores), the discovery of twenty-two new satellites including three at Jupiter, three at Saturn, ten at Uranus, and six at Neptune, Io was found to have active volcanism (the only other Solar System body than Earth to be confirmed), Triton was found to have active geyser-like structures and an atmosphere, Auroral Zones (where gases become excited after being hit by solar particles) were discovered at Jupiter, Saturn, and Neptune, Jupiter was found to have rings, Neptune, originally thought to be too cold to support such atmospheric disturbances, had large-scale storms. |
| Date |
UNKNOWN |
| NASA Center |
Jet Propulsion Laboratory |
|
Voyager 2 Launch
| Title |
Voyager 2 Launch |
| Full Description |
Voyager 2 was launched August 20, 1977, sixteen days before Voyager 1 aboard a Titan-Centaur rocket. Their different flight trajectories caused Voyager 2 to arrive at Jupiter four months later than Voyager 1, thus explaining their numbering. The initial mission plan for Voyager 2 specified visits only to Jupiter and Saturn. The plan was augmented in 1981 to include a visit to Uranus, and again in 1985 to include a flyby of Neptune. After completing the tour of the outer planets in 1989, the Voyager spacecraft began exploring interstellar space. The Voyager mission has been managed by NASA's Office of Space Science and the Jet Propulsion Laboratory. |
| Date |
08/20/1977 |
| NASA Center |
Kennedy Space Center |
|
Saturn Seen from Far and Nea
…
| Title |
Saturn Seen from Far and Near |
|
Saturn Seen from Far and Nea
…
| Title |
Saturn Seen from Far and Near |
|
A86-7007
Photographer : JPL Range : 1
…
1/14/81
| Description |
Photographer : JPL Range : 12.9 million km. ( 8.0 million miles ) P-29467B/W Time lapse Voyager 2 images of Uranus show the movement of two small, bright, streaky clouds, the first such features ever seen on the planet. The clouds were detected in this series of orange filtered images, over a 4.6 hour interval ( from top to bottom ). Uranus, which is tipped on its side with respect to the other planets, is rotating in a counter-clockwise direction, with its pole of rotation near the center of the disk, as are the two clouds seen here as bright streaks. The larger of the two clouds is ata lattitude of 33 degrees. The smaller cloud, seen faintly in the three lower images, lies at 26 degrees ( a lower alttitude and hence closer to the limb). Their counterclockwise periods of rotation are 16.2 and 16.9 hours, respectively. This difference implies that the lower lattitude feature is lagging behind the higher latitude feture at a speed of almost 100 meters pers second (220 mph). Latitudinal bands are also visible in these images, the faint bands, more numerous now then in previous Voyager images from longer range, are concentric with the pole rotation. thatis, they circle the planet in lines of contant latitude. |
| Date |
1/14/81 |
|
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. |
|
Saturn, Rings, and Two Moons
| Title |
Saturn, Rings, and Two Moons |
| Explanation |
This image of Saturn was made by NASA's robot spacecraft Voyager [ http://nssdc.gsfc.nasa.gov/planetary/voyager.html ] 2 as it began to explore the Saturn system in 1981. Saturn's famous rings are visible along with two of its moons, Rhea and Dione which appear as faint dots in the right and lower right part of the picture. Astronomers believe that Saturn's moons play a fundamental role in sculpting its elaborate ring system. For more information about the picture see the NASA, JPL press release. [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/saturn.txt ] |
|
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. |
|
Saturn, Rings, and Two Moons
| Title |
Saturn, Rings, and Two Moons |
| Explanation |
NASA's robot spacecraft Voyager [ http://antwrp.gsfc.nasa.gov/apod/ap960629.html ] 2 made this image [ http://nssdc.gsfc.nasa.gov/photo_gallery/caption/saturn.txt ] of Saturn [ http://www.seds.org/nineplanets/nineplanets/saturn.html ] as it began to explore the Saturn system [ http://www.jpl.nasa.gov/cassini/Images/astro/23209.html ] in 1981. Saturn's famous rings [ http://ringside.arc.nasa.gov/www/saturn/saturn.html ] are visible along with two of its moons, Rhea [ http://bang.lanl.gov/solarsys/rhea.htm ] and Dione [ http://antwrp.gsfc.nasa.gov/apod/ap951009.html ] which appear as faint dots on the right and lower right part of the picture. Astronomers believe that Saturn's moons play a fundamental role in sculpting its elaborate ring system [ http://newproducts.jpl.nasa.gov/saturn/back.html ]. A robot spacecraft named Cassini [ http://www.jpl.nasa.gov/cassini/ ] was launched [ http://antwrp.gsfc.nasa.gov/apod/ap971016.html ] last October and is expected to rendezvous [ http://www.jpl.nasa.gov/cassini/Mission/tour.html ] with the giant gas planet in 2004. |
|
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. |
|
Night side of Titan
| Title |
Night side of Titan |
| Description |
Voyager 2 obtained this wide-angle image of the night side of Titan on Aug. 25 at a high phase angle of 154` and a range of 907,000 kilometers (563,000 miles). Green and violet images were combined to make this photograph. The result is a view of the extended atmosphere of this satellite of Saturn, the bright orangish ring being caused by the atmosphere's scattering of the incident sunlight. The bluish outer ring is further evidence of scattering by the submicron size particles that extend several hundred kilometers above the main clouds. This type of photograph is a direct indication of Titan's extensive atmosphere. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena. |
| Date |
08.27.1981 |
|
Photograph of Saturns' satel
…
| Title |
Photograph of Saturns' satellite Tethys |
| Description |
This Voyager 2 photograph of Tethys shows objects about 5 kilometers (3 miles) in size and is one of the best images of the Saturnian satellite returned by the spacecraft or its predecessor, Voyager 1. Voyager 2 obtained this picture Aug. 26 from a range of 282,000 kilometers (175,000 miles). It has been specially processed by computer to bring out fine detail on the surface. A boundary between heavily cratered regions (top right) and more lightly cratered areas (bottom right) is very similar to boundaries on the moons Dione and Rhea, indicating a period of internal activity early in Tethys' history that partially resurfaced the older terrain. The large crater in the upper right lies almost on the huge trench system that girdles nearly three-fourths of the circumference of the satellite. The trench itself is seen in this image as a linear set of markings to the lower left of the crater. The trench, several kilometers deep, is indicative of a cold, stiff ice crust at the time of its formation. Formation of this trench system could have resulted from the expansion of Tethys as its warm interior froze. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.31.1981 |
|
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 - Enceladus from a di
…
| Title |
Saturn - Enceladus from a distance of 119,000 kilometers (74,000 miles) |
| Description |
This Voyager 2 mosaic of Enceladus was made from images taken through the clear, violet and green filters Aug. 25, 1981, from a distance of 119,000 kilometers (74,000 miles). In many ways, the surface of this satellite of Saturn resembles that of Jupiter's Galilean satellite Ganymede. Enceladus, however, is only one-tenth Ganymede's size. Some regions of Enceladus show impact craters up to 35 kilometers (22 miles) in diameter, whereas other areas are smooth and uncratered. Linear sets of grooves tens of kilometers long traverse the surface and are probably faults resulting from deformation of the crust. The uncratered regions are geologically young and suggest that Enceladus has experienced a period of relatively recent internal melting. The rims of several craters near the lower center of the picture have been flooded by the smooth terrain. The satellite is about 500 kilometers (310 miles) in diameter and has the brightest and whitest surface of any of Saturn's satellites. Features as small as 2 kilometers (1.2 miles) are visible in this highest-resolution view of Enceladus. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.28.1981 |
|
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 - Tethys from 594,000
…
| Title |
Saturn - Tethys from 594,000 kilometers (368,000 miles) away. |
| Description |
Voyager 2 obtained this image of Tethys on Aug. 25, when the spacecraft was 594,000 kilometers (368,000 miles) from this satellite of Saturn. This photograph was compiled from images taken through the violet, clear and green filters of Voyager's narrow-angle camera. Tethys shows two distinct types of terrain--bright, densely cratered regions, and relatively dark, lightly cratered planes that extend in a broad belt across the satellite. The densely cratered terrain is believed to be part of the ancient crust of the satellite, the lightly cratered planes are thought to have been formed later by internal processes. Also clearly seen is a trough that runs parallel to the terminator (the day-night boundary, seen at right). This trough is an extension of the huge canyon system Voyager 1 saw last fall. This system extends nearly two-thirds the distance around Tethys. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif. |
| Date |
08.27.1981 |
|
|
