Titan Surface features



The surface of Titan has been described as "complex, fluid-processed, geologically young".Titan has been around since the Solar System's formation, but its surface is much younger, between 100 million and 1 billion years old. Geological processes may have reshaped Titan's surface. Titan's atmosphere is twice as thick as Earth's, making it difficult for astronomical instruments to image its surface in the visible light spectrum.
The Cassini spacecraft is using infrared instruments, radar altimetry and synthetic aperture radar imaging to map portions of Titan during its close fly-bys. The first images revealed a diverse geology, with both rough and smooth areas. There are features that may be volcanic in origin, disgorging water mixed with ammonia onto the surface. However, there is also evidence that Titan's ice shell may be substantially rigid, which would suggest little geologic activity.

There are also streaky features, some of them hundreds of kilometers in length, that appear to be caused by windblown particles. Examination has also shown the surface to be relatively smooth; the few objects that
seem to be impact craters appeared to have been filled in, perhaps by raining hydrocarbons or volcanoes. Radar altimetry suggests height variation is low, typically no more than 150 meters. Occasional elevation changes of 500 meters have been discovered and Titan has mountains that sometimes reach several hundred meters to more than 1 kilometer in height.

Titan's surface is marked by broad regions of bright and dark terrain. These include Xanadu, a large, reflective equatorial area about the size of Australia. It was first identified in infrared images from the Hubble Space Telescope in 1994, and later viewed by the Cassini spacecraft. The convoluted


region is filled with hills and cut by valleys and chasms. It is criss-crossed in places by dark lineaments—sinuous topographical features resembling ridges or crevices. These may represent tectonic activity, which would indicate that Xanadu is geologically young. Alternatively, the lineaments may be liquid-formed channels, suggesting old terrain that has been cut through by stream systems. There are dark areas of similar size elsewhere on Titan, observed from the ground and by Cassini; it had been speculated that these are methane or ethane seas, but Cassini observations seem to indicate otherwise.












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