Titanic Saturn

barakn writes "Using the Crab Nebula as an x-ray source, scientists have observed Titan's x-ray shadow to get a preliminary estimate of the extent of its outer atmosphere. On the same page, another article discusses the possibility that the hydrocarbon seas of Titan bear waves, albeit slow-moving and widely spaced, 7 times higher than waves on Earth (additional wave links here, here, and here). And Cassini-Huygens has snapped a photo of Saturn showing "two small, faint dark spots" in the southern hemisphere (this link has convenient arrows pointing at them, or here). Cassini-Huygens will achieve Saturn orbit insertion on July 1st. Huygens will detach and enter Titan's atmosphere in January, 2005."

Comments

Re:A thick atmosphere in low gravity?

[CheshireCatCO]

I don't know who told you that, but that's totally wrong. There's no way a significant fraction of the atmosphere would ever be re-accreted by the planet from a torus, first of all. (Io has a very distinct torus and its atmosphere is all by non-existant.)

Second of all, we have yet to observe any Titan-torus, last I heard. (About two weeks ago, a comment made from one of the Cassini principle investigators.) If there's so much gas there, why can't we see it?

Finally, the reason Titan can hold a thick atmosphere is, as some already stated, because it's so bloody cold. You can do the simple atmospheric calculations and show that at the tempertures of Titan, it can hold that atmosphere pretty nicely.

A good place to look for details is _The New Solar System_, Beatty, Petersen, and Chaikin, editors.

Copying an old experiment

[techno-vampire]

Back in the 80's, JPL changed the course of Voyager I to go behind Titan. The distance at which the signal started to drop, and the rate it dropped at gave us very good measurements of the atmosphere's depth and density. In fact, if the probe's distance from the center of Titan had been cut in half, it would have crashed. That's right, it was less than two radii out! I know, because I worked with the man who wrote the navagation system they used back then (The late Daniel J. Alderson.) and stll know, slightly, the man who used it for this, Bob Ceserone.