[X] My Assistant

[Guest_BruceMoomaw_*]

http://uanews.org/cgi-bin/WebObjects/UANew...ArticleID=11813

Could this thing possibly be a fresh volcanic dike of uprising water/ammonia
ice (like the light-colored dome Huygens imaged that seems to be surrounded
by geothermal methane springs)? If so, however, it must have cooled off by
now.

[JRehling]

http://uanews.org/cgi-bin/WebObjects/UANew...ArticleID=11813

Could this thing possibly be a fresh volcanic dike of uprising water/ammonia
ice (like the light-colored dome Huygens imaged that seems to be surrounded
by geothermal methane springs)?  If so, however, it must have cooled off by
now.

The larger structure looks a lot like Artemis Chasma on Venus. While Artemis Corona is obviously a circular feature, it is much more well defined in the southern half, and if you set a threshold for altitude just right, you see a "smile" shape there, too. It also happens to be at about the same latitude as Titan's smile, and in the same orientation!

Given the semicircular shape, I would guess that Titan's smile shows a large area of mantle mobility (up or down -- that's hard to settle), whose circumference featured tectonic activity that somehow colored the surface around it, and was, like Artemis, better defined in one half than the other.

[Guest_Richard Trigaux_*]

It could be anything else. For instance a "threshold" in altitude, from a volcanic cardeira or meteor impact, could be made visible by high altitude snow. What kind of snow, I wonder, there are many candidates, in the list of hydrocarbons.


Maybe if we look among the simple hydrocarbons, the one with the adequate fusion temp, and get its infrared spectra...

It could be also the result of a local snow storm or hail storm. In a previous discution it was sait that, due to the low heat input into the Titan system, and the scarcity of fluids (mainly methane) there could be only a very dry weather with, from times to times, very violent rain falls. Eventually there could be localized hail or snow storms, which result could be still visible years after, as the snow or hail melts only very slowly. But these ices or snows cannot be methane, which cannot freeze on Titan, so it may be something else, eventually more or less mixed with methane.