Starship Asterisk*

http://en.wikipedia.org/wiki/Titan_%28moon%29 wrote:

Composite map of Titan's surface.

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<<The surface of Titan has been described as "complex, fluid-processed, [and] geologically young". The Cassini spacecraft has used radar altimetry and synthetic aperture radar (SAR) imaging to map portions of Titan during its close fly-bys of the moon. The first images revealed a diverse geology, with both rough and smooth areas. There are features that seem volcanic in origin, which probably disgorge water mixed with ammonia. 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. 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.>>

Bruce McCurdy wrote:In the Namibia half of the APOD the white splotches are clearly clouds, as they have analog shadows on the ground (the dark splotches). Are the white splotches on the Titan half of the APOD also clouds in its atmosphere? Or some sort of surface feature?

[b][i]Communications[/i][/b][/url]: [url=http://asterisk.apod.com/viewtopic.php?f=31&t=20460][b][i]Blowing in the Wind[/i][/b] wrote:The bright features (top) are not clouds but topographic features.

biddie67 wrote:With Titon revolving so slowly, it's hard to see how the winds could change direction and strength enough to create the strange sand dune patterns even with the extra (minor?) heat input from an equinox.

bystander wrote:Communications: Blowing in the Wind

http://en.wikipedia.org/wiki/Namib_Desert wrote:
<<Having endured arid or semi-arid conditions for at least 55 million years, the Namib Desert is considered to be the oldest desert in the world. The name "Namib" is of Nama origin and means vast. The Namib's aridity is caused by the descent of dry air of the Hadley Cell, cooled by the cold Benguela current along the coast. It has less than 10 mm of rain annually and is almost completely barren. A huge group of sand dunes, which at more than 300 meters high are among the tallest sand dunes in the world. The complexity and regularity of dune patterns in its dune sea have attracted the attention of geologists for decades. They still remain poorly understood.>>

http://en.wikipedia.org/wiki/Sossusvlei wrote:
<<Sossusvlei is a clay pan in the central Namib Desert, lying within the Namib-Naukluft National Park, Namibia. Fed by the Tsauchab River, it is known for the high, red sand dunes which surround it forming a major sand sea. Vegetation, such as the camelthorn tree, is watered by infrequent floods of the Tsauchab River, which slowly soak into the underlying clay.>>

owlice wrote:Orin, wasn't that something?!! And as it starts to go over, the brake lights come on...! A natural reaction, I suppose, though a fruitless one in this case!