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Hotei Regio

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RE: Titan

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Credit: NASA/JPL/USGS


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Cassini's radar mapper has obtained stereo views of close to 2 percent of Titan's surface during 19 flybys over the last five years. The process of making topographic maps from images is just getting started, but the results already reveal some of the diversity of Titan's geologic features.
The prominent, roughly circular feature in the western part of this image is an area known as Ganesa Macula. This 180-kilometer-wide feature crudely resembles steep-sided volcanic domes on Venus that were imaged with the NASA Magellan spacecraft in the 1990s. It was therefore hypothesised initially to be a cryovolcanic feature. The topographic map derived from radar stereo shows that Ganesa as a whole is not elevated, as would be expected for a volcano. Instead, it is tilted (low in the west, high along the eastern margin). Other high and low areas with north-south trending margins alternate to the east of Ganesa. Low areas are consistently filled by radar-bright (rough) channels and flow deposits. The largest of these, in the centre of the map with two bright channels leading to triangular fan structures on its western margin, is known as Leliah Fluctus. Although Ganesa Macula could have originated as a cryovolcanic feature (or perhaps as an impact crater, either of which would account for its distinct circular outline), it appears to have been extensively modified by both tectonic (faulting) and fluvial (erosion by fluids derived from rainfall) processes.
The region shown here is centred near 50 degrees north latitude, 80 degrees west longitude, and is about 1,480 kilometres across. The maps are in equirectangular projection with north at the top. The images used for mapping were acquired during flybys on Oct. 26, 2004, and Jan. 13, 2007 (known as Ta and T23). The Ta image is shown in black and white at the top. It has a pixel spacing of 351 metres. Below, the same image is shown with colour coding to indicate elevations, as shown by the colour bar at left. The total range of relief from purple (low) to red (high) is 1,000 metres.

Source NASA

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Cassini Provides Virtual Flyover of Saturn's Moon Titan
"Fly me to the moon" -- to Saturn's moon Titan, that is. New Titan movies and images are providing a bird's-eye view of the moon's Earth-like landscapes.
The new flyover maps show, for the first time, the 3-D topography and height of the 1,200-metre mountain tops, the north polar lake country, the vast dunes more than 100 metres high that crisscross the moon, and the thick flows that may have oozed from possible ice volcanoes.

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Cassini Maps Global Pattern of Titan's Dunes
Titan's vast dune fields, which may act like weather vanes to determine general wind direction on Saturn's biggest moon, have been mapped by scientists who compiled four years of radar data collected by the Cassini spacecraft.
Titan's rippled dunes are generally oriented east-west. Surprisingly, their orientation and characteristics indicate that near the surface, Titan's winds blow toward the east instead of toward the west. This means that Titan's surface winds blow opposite the direction suggested by previous global circulation models of Titan.

"At Titan there are very few clouds, so determining which way the wind blows is not an easy thing, but by tracking the direction in which Titan's sand dunes form, we get some insight into the global wind pattern. Think of the dunes sort of like a weather vane, pointing us to the direction the winds are blowing" - Ralph Lorenz, Cassini radar scientist at Johns Hopkins University Applied Physics Laboratory in Laurel, Md..

A paper based on these findings appeared in the Feb. 11 issue of Geophysical Research Letters.

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Fensal, a magnificent mansion in Norse mythology, is home to Bazaruto Facula and Sinlap on Saturn's largest moon.
Two dark bands stretch across the moon Titan in this image: Fensal north of the equator and Aztlan south of the equator. The eastern part of Fensal features the white circle of Bazaruto Facula. This bright 215-kilometre wide feature is visible just below the center of the image. Inside it is Sinlap, a dark 80-kilometre wide crater.

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Credit: NASA/JPL/Space Science Institute

This view looks toward the Saturn-facing side of Titan (5150 kilometres across). North on Titan is up and rotated 24 degrees to the right.

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Today, the Cassini spaceprobe will make a close flyby (T-50) of Titan to investigate the moon's mid-southern latitudes.
At closest approach, at only 960 kilometres distance, the Cassini onboard RADAR will sweep across the Tsegihi Mountains.

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Recent images of Titan from NASA's Cassini spacecraft affirm the presence of lakes of liquid hydrocarbons by capturing changes in the lakes brought on by rainfall.
For several years, Cassini scientists have suspected that dark areas near the north and south poles of Saturn's largest satellite might be liquid-filled lakes. An analysis published today in the journal Geophysical Research Letters of recent pictures of Titan's south polar region reveals new lake features not seen in images of the same region taken a year earlier. The presence of extensive cloud systems covering the area in the intervening year suggests that the new lakes could be the result of a large rainstorm and that some lakes may thus owe their presence, size and distribution across Titan's surface to the moon's weather and changing seasons.
The high-resolution cameras of Cassini's Imaging Science Subsystem (ISS) have now surveyed nearly all of Titan's surface at a global scale. An updated Titan map, being released today by the Cassini Imaging Team, includes the first near-infrared images of the leading hemisphere portion of Titan's northern "lake district" captured on Aug. 15-16, 2008. (The leading hemisphere of a moon is that which always points in the direction of motion as the moon orbits the planet.) These ISS images complement existing high-resolution data from Cassini's Visible and Infrared Mapping Spectrometer (VIMS) and RADAR instruments.

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The Cassini spaceprobe will make a close flyby (960 km) of Titan on the 7th February, 2009.

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A spacecraft has captured an image of what may be the first drop of liquid ever observed on an extraterrestrial surface.
Among the pictures snapped by the Huygens probe after landing on Saturn's moon Titan in 2005, one appears to show a dewdrop made of methane that briefly formed on the edge of the probe itself. Scientists think heat from the probe caused humid air to rise and condense on the cold edge of the craft.
Though Huygens had a hand in producing it, the methane drop is still the first liquid directly detected at the surface anywhere beyond Earth.
Like Earth, Titan has clouds, lakes, and river channels, and it may be the only other place in the solar system where liquid evaporates from the surface and returns as rain

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