Browse All : Voyager and Cassini from 1981

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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.
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
Enceladus: Trailing Hemisphe …
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
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
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
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 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.
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)
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.
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.
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.
Video greeting to NASA JPL b …
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
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
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)
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
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.
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
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
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
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
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.
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.
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
Wide-Angle Image of Saturn's …
Title Wide-Angle Image of Saturn's Rings
Description This wide-angle image of Saturn's rings was taken Aug. 26 just before Voyager 2's crossing of the plane of these complex structures. The spacecraft was 103,000 kilometers (64,000 miles) from the rings when it acquired this image. This extremely oblique view of the bright side of the rings highly magnifies features near the bottom of the picture and compresses features across to the other side of the west ansa (the western edge of the loop in the rings). Starting from the bottom, one can see the F-ring, the A-ring with the Encke Gap, the Cassini Division (the narrow dark band at center), the B-ring and the C-ring. The high-contrast bright and dark areas of the C-ring are seen at right, then, continuing upward, come the B- and A-rings straddling the Cassini Division and a very foreshortened view of the A-ring. The bright streaks in the B-ring are the spokes in forward-scattered light. The Voyager project is managed for NASA by the Jet Propulsion Laboratory, Pasadena, Calif.
Date 08.29.1981
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 ].
Seasonal Differences
PIA06121
Saturn
Imaging Science Subsystem - …
Title Seasonal Differences
Original Caption Released with Image Cassini's finely tuned vision reveals seasonal differences in the global haze that envelopes Titan in this narrow angle camera image taken on Oct. 24, 2004. The picture was taken through a filter sensitive to strong absorption by methane gas (wavelengths centered at 889 nanometers). Here, the northern hemisphere of Titan is notably brighter than the southern hemisphere, because there is more haze in the north. The presence of haze in the northern hemisphere was also observed in images returned by NASA's Voyager spacecraft in 1981. The haze distribution was reversed, north to south, in observations taken by NASA's Hubble Space Telescope from 1994 to 2000. The image was taken from a distance of 1.08 million kilometers (675,000 miles) from Titan. The image scale is 6.52 kilometers (4.05 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 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/ ].
Enceladus: Trailing Hemisphe …
PIA08353
Saturn
Imaging Science Subsystem - …
Title Enceladus: Trailing Hemisphere
Original Caption Released with Image 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 PIA06191 [ http://photojournal.jpl.nasa.gov/catalog/PIA06191 ]), 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/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/ ].
Watching Saturn's Winds
PIA07670
Sol (our sun)
Imaging Science Subsystem - …
Title Watching Saturn's Winds
Original Caption Released with Image 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 [ http://saturn.jpl.nasa.gov ]. The Cassini imaging team homepage is at http://ciclops.org [ http://ciclops.org ].
On the Final Frontier
PIA08388
Saturn
Imaging Science Subsystem - …
Title On the Final Frontier
Original Caption Released with Image 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 PIA08362 [ http://photojournal.jpl.nasa.gov/catalog/PIA08362 ] and PIA08361 [ http://photojournal.jpl.nasa.gov/catalog/PIA08361 ]). 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 [ http://photojournal.jpl.nasa.gov/catalog/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 [ http://photojournal.jpl.nasa.gov/catalog/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/home/index.cfm [ http://saturn.jpl.nasa.gov ]. The Cassini imaging team homepage is at http://ciclops.org [ http://ciclops.org ].
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