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Two Sides of Dunes
| Description |
Two Sides of Dunes |
| Full Description |
This pair of images, taken by the Cassini spacecraft radar mapper on two different Titan passes on Dec. 11, 2006 (T21 left), and Oct. 29, 2005 (T8 right), represent two different views of a field of dunes located near 9.4 degrees south latitude by 290 degrees west longitude. The images were taken in synthetic aperture mode and have a resolution of approximately 500 meters (1,640 feet). North is toward the top of both images, and each image is approximately 400 kilometers (250 miles) long by 275 kilometers (170 miles) wide. The images are different only because the radar instrument illuminated the dunes from different directions. Acting somewhat like a flash camera, the radar sends out microwave pulses and makes an image from the pulses after they are reflected back. Imagine that both the "camera" and the "flash" come from the left in the left image and from the top in the right image. Most obvious differences are seen in the large bright feature at the center of both images. At left, its left edge is brighter, emphasizing the more steep slopes there. Farther left, the dunes are more clearly defined in the right image as their faces are caught by the illumination. However, since the dunes are visible in both images, it is likely that the materials making up the dark and light stripes are also somehow different. More detailed studies of how materials on Titan reflect and scatter at different angles are giving us clues about what different materials might be present in this cold and distant world. For more information about dunes on Titan, see Dunes Galore. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
January 11, 2007 |
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Titan Dunes over Possible Cr
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| Description |
Titan Dunes over Possible Craters (T23) |
| Full Description |
This radar image of Titan's well-known dunes is distinctive because it may show an age relationship between different classes of features on the surface of this frigid world. Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, three kinds of terrain can be seen. Throughout the image, the fine striping has been identified as dunes, possibly made from organic material and formed by wind activity. Dunes are a common landform on Titan (see Two Sides of Dunes and Swimming in Dunes). The bright material at the lower right of the image is interpreted as being topographically higher than the dunes that go around it, and several circular features seen at the top center may be craters that are slowly being buried by the dunes. Since the dunes seem to lie over the craters, the dune activity probably occurred later in time. This image was taken in synthetic aperture mode and has a resolution of approximately 350 meters (1,150 feet). North is toward the top left corner of the image, which is approximately 160 kilometers (100 miles) long by 150 kilometers (90 miles) wide. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. *Credit:* NASA/JPL |
| Date |
January 24, 2007 |
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Titan Flyby - Feb. 22, 2007
| Description |
T25 flyby art |
| Full Description |
Cassini Flyby to Crisscross Familiar Terrain On Cassini's next pass of Titan on Feb. 22 (SCET), the radar mapper will image Titan's surface and crisscross over six previously mapped areas. Cassini's radar will focus on Titan's north pole region, where lakes have been spotted. The spacecraft will swoop from 30 degrees south latitude, all the way up to 85 degrees north longitude. On this second view of the lakes region, scientists will look for changes and perhaps spot new lakes. The overlap of images over the same area allows the use of stereo techniques to determine the height of surface features. + View Flyby Page |
| Date |
February 15, 2007 |
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A New Crater on Titan?
| Description |
This radar image of Titan shows a semi-circular feature that may be part of an impact crater. Very few impact craters have been seen on Titan so far, implying that the surface is young. |
| Full Description |
This radar image of Titan shows a semi-circular feature that may be part of an impact crater. Very few impact craters have been seen on Titan so far, implying that the surface is young. Each new crater identified on Titan helps scientists to constrain the age of the surface. Taken by Cassini's radar mapper on Jan. 13, 2007, during a flyby of Titan, the image swath revealed what appeared to be the northernmost half of an impact crater. This crater is roughly 180 kilometers (110 miles) wide. Only three impact craters have been identified on Titan and several others, like this one, are likely to also have been caused by impact. The bright material is interpreted to be part of the crater's ejecta blanket, and is likely topographically higher than the surrounding plains. The inner part of the crater is dark, and may represent smooth deposits that have covered the inside of the crater. This image was taken in synthetic aperture mode and has a resolution of approximately 350 meters (1,150 feet). North is toward the top left corner of the image, which is approximately 240 kilometers (150 miles) wide by 140 kilometers (90 miles) high. The image is centered at about 26.5 degrees north and 9 degrees west. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
February 16, 2007 |
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Radar Sees Lakes in Titan's
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| Description |
Cassini's radar instrument finds lakes in the southern hemisphere of Titan during the most recent Titan flyby. |
| Full Description |
Cassini's radar instrument finds lakes in the southern hemisphere of Titan during the most recent Titan flyby. This is the first confirmation of lakes in the southern hemisphere with the radar instrument. Hundreds of lakes have already been discovered and imaged by radar at Titan's north pole. This finding is important to scientists who are trying to understand how Titan's environment works. Cassini completed its 37th flyby of Saturn's moon Titan on Oct. 2, 2007, allowing the Cassini Titan Radar Mapper to obtain this southernmost image to date. Shown here is a portion of the image swath and an inset with details of a small portion in false color. Titan's south pole is at the bottom center. The nature and similarities between the northern and southern near-polar regions supports the idea that much of Titan's poles are climate-driven. A few small dark patches - liquid-hydrocarbon-filled lakes - stand out, at about 70 degrees south, and are highlighted in the insert (lakes are colored blue). Other features in the scene include broad, steep-sided depressions adjoined to sinuous depressions, interpreted to be empty topographic basins or drained lakes fed by channels, and complex mottled terrain, akin to those at similar northern latitudes. Similarities in features between northern and southern hemispheres imply that the climatic conditions are also similar. The image shown here is a 1.4-kilometer (0.87-mile) resolution, 2,250-kilometer (1,400 mile) subsection of a 4,500-kilometer (2,800-mile) long swath, which is 150 kilometers (93 miles) wide at the narrowest point. The insert is 90 by 90 kilometers (56 by 56 miles), centered at 70.5 degrees south and 113.9 degrees west. Future southern flybys will image closer to the pole and are expected to show more lakes. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm . Credit: NASA/JPL/USGS |
| Date |
October 11, 2007 |
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Ganesa Macula
| Description |
This radar image of Titan shows Ganesa Macula, interpreted as a cryovolcano (ice volcano), and its surroundings. |
| Full Description |
This radar image of Titan shows Ganesa Macula, interpreted as a cryovolcano (ice volcano), and its surroundings. Cryovolcanism is thought to have been an important process on Titan and may still be happening today. This mosaic was made from images obtained by the Cassini radar mapper on two flybys. The lower part of the image was from the flyby on Oct. 26, 2004, while the upper part was from the Jan. 13, 2007, flyby. Ganesa macula is the dark circular feature seen on the lower left of the mosaic. Bright rounded features, interpreted as cryovolcanic flows, are seen towards the top and the right of the mosaic. This image mosaic was taken in synthetic aperture mode. The resolution of the images is approximately 350 meters (1,150 feet). North is toward the top. The image mosaic is about 570 kilometers (354 miles) wide and 390 kilometers (240 miles) high. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm. Credit: NASA/JPL |
| Date |
February 16, 2007 |
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Titan (T30) Viewed by Cassin
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PIA09218
Saturn
Radar Mapper
| Title |
Titan (T30) Viewed by Cassini's Radar - May 12, 2007 |
| Original Caption Released with Image |
This north polar image of Titan was acquired by Cassini?s radar instrument on May 12, 2007. Stretching from 69 degrees north, 329 degrees west to 33 degrees north, 227 degrees west, this swath gently curves from west-to-east at the left end to north-to-south at the right. It is more than 2,700 kilometers (1,678 miles) long and varies from 200 to 500 kilometers (124 to 310 miles) in width, covering the southern extreme of a large dark area previously imaged by the Imaging Science Subsystem (see PIA08365 [ http://photojournal.jpl.nasa.gov/catalog/PIA08365 ]). The thin white stripe at immediate left is an artifact related to the instrument?s multi-beam operation, throughout the swath there are some near-vertical stripes that are also artifacts. As displayed here, the extreme left end of the image shows the west margin of a dark area interpreted to be a lake of liquid methane and probably ethane, with obvious shore-like features, such as bays, inlets and islands. Radar images show smooth areas as dark, and this lake is among the darkest areas seen so far on Titan. The eastern margin of the lake is similarly complex, and some of the shoreline features seem related to ridges and lower topography on the shore, as if the liquid in the lake has filled lower-lying areas between ridges. Some of these channels drain into the lake, while others go into a slightly brighter, more uniform area that may be connected to the lake just off the lower edge of the image (for more details on this area, see PIA09211 [ http://photojournal.jpl.nasa.gov/catalog/PIA09211 ]). Farther to the right, moving southward, a complex region of ridges and channels transitions to more subdued landforms with circular or lobate features, some of which have raised rims. The terrain toward the right of the image is rougher, with topographic depressions that resemble dried lakebeds, lacking the dark material seen in the lakes farther north. Toward the right end of the image, farthest from the north pole, a series of long, low depressions is seen against a relatively dark background. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov/home/index.cfm [ http://saturn.jpl.nasa.gov ]. |
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Coasts and Drowned Mountains
PIA09211
Saturn
Radar Mapper
| Title |
Coasts and Drowned Mountains |
| Original Caption Released with Image |
On May 12, 2007, Cassini completed its 31st flyby of Saturn's moon Titan, which the team calls T30. The radar instrument obtained this image showing the coastline and numerous island groups of a portion of a large sea, consistent with the larger sea seen by the Cassini imaging instrument (see http://photojournal.jpl.nasa.gov/catalog/PIA08930 [ http://photojournal.jpl.nasa.gov/catalog/PIA08930 ]). Like other bodies of liquid seen on Titan, this feature reveals channels, islands, bays, and other features typical of terrestrial coastlines, and the liquid, most likely a combination of methane and ethane, appears very dark to the radar instrument. What is striking about this portion of the sea compared to other liquid bodies on Titan is the relative absence of brighter regions within it, suggesting that the depth of the liquid here exceeds tens of meters (tens of yards). Of particular note is the presence of isolated islands, which follow the same direction as the peninsula to their lower right, suggesting that they may be part of a mountain ridgeline that has been flooded. This is analogous to, for example, Catalina Island off the coast of Southern California. The image as shown is about 160 kilometers (100 miles) by 270 kilometers (170 miles) at 300-meter (980-foot) resolution. The image is centered near 70 degrees north latitude and 310 west longitude. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/home/index.cfm [ http://saturn.jpl.nasa.gov ]. |
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Titan (T28) Viewed by Cassin
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PIA09217
Saturn
Radar Mapper
| Title |
Titan (T28) Viewed by Cassini's Radar-- April 10, 2007 |
| Original Caption Released with Image |
), these lakes are likely connected, and may form part of a larger sea. Brighter areas within the lakes may represent the lake bottom - at the radar's 2-centimeter wavelength, it is possible that the liquid is transparent for many tens of meters (tens of yards) to the radar, allowing a reflection to be returned from the lake bottom. 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 was designed, developed and assembled at JPL. The radar instrument was built by JPL and the Italian Space Agency, working with team members from the United States and several European countries. For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov/home/index.cfm [ http://saturn.jpl.nasa.gov ]., Cassini's radar instrument obtained another in its series of north polar swaths of Titan on April 10, 2007. This image exposes more of the transition between the mid-latitudes and the polar area, and extends coverage of the lakes region previously described in PIA09182 [ http://photojournal.jpl.nasa.gov/catalog/PIA09182 ]. This swath begins at 20 degrees south, 37 degrees west, continuing approximately north-northeast. Although it appears to be straight in this image, its path on Titan curves gently toward the east until it reaches 80 degrees north at 300 degrees west, then it turns south and ends at 51 degrees north, 213 degrees west. The swath width varies from about 200 kilometers (120 miles) at its center to about 500 kilometers (310 miles) at the ends, and is more than 6,700 kilometers (4,100 miles) long. Beginning at the left end of the image as shown, we see the dark sinuous features previously interpreted to be dunes, interspersed with bright features that appear to be higher. In some cases the dunes seem to bend around the bright features, and in others they may be climbing up onto them, both behaviors are commonly seen in dune fields on Earth. About one-third of the way through the swath, the dunes become rare and then disappear, to be replaced by more linear features. Some of these have rounded and brighter ends, similar to lava flows on Earth (in synthetic aperture radar images, rougher features appear as bright). Just past the midway point, we find relatively flat and featureless terrain with some structures that also resemble flow fronts, followed by a complex area of semi-circular to irregular depressions that may have formed by collapse. These give way to the lakes at the northernmost portion. Here T28 overlaps with the T25 synthetic aperture radar swath (see PIA09182 [ http://photojournal.jpl.nasa.gov/catalog/PIA09182 ]), offering stereo coverage that will be used to determine feature heights. The lakes, which are thought to be filled with a combination of methane and ethane, have complex shorelines that often include channels. Some of these channels have well-developed tributary systems and drain many thousands of square kilometers of the surrounding terrain. As shown in the mosaic (see PIA08365 [ http://photojournal.jpl.nasa.gov/catalog/PIA08365 ] |
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