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Mr. Milton Banana
2005-Jul-30, 01:30 PM
...what would it look like?

I imagine it would look similar to a snow shower, except you have big drops of liquid methane floating down to the surface.

:-k

Superluminal
2005-Jul-30, 02:21 PM
I would imagine that you would need a well insulated raincoat. :D

Ilya
2005-Jul-30, 03:25 PM
The drops would fall slowly enough for a human eye to discern their shape. Raindrops are not teardrop-shaped, but are flattened spheres. Largest raindrops are almost Freesbie-shaped -- fat disks with an indentation in the middle. On Earth all that can be seen only with high-speed film. On Titan it would be obvious.

Rain Dog
2005-Jul-30, 08:54 PM
I don’t think there’d be discernable droplets at all. Methane is non-polar, so the liquid should have almost no surface tension. With nothing to hold droplets together, I think the result would be something like mist.

grant hutchison
2005-Jul-30, 10:58 PM
I don’t think there’d be discernable droplets at all. Methane is non-polar, so the liquid should have almost no surface tension. With nothing to hold droplets together, I think the result would be something like mist.The surface tension of liquid methane is known - 17 mN/m - which is around a quarter of water's. Not too bad.
You can read the theory in The life, death and afterlife of a raindrop on Titan (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1993P%26SS...41..647L&db_key=AST ), by Ralph Lorenz.

Grant Hutchison

Rain Dog
2005-Jul-31, 01:14 AM
Terminal descent velocities for drops of various sizes at different altitudes are presented, and it is found that the largest raindrops may be larger than those on Earth (9.5 mm diameter vs 6.5 mm diameter)Emphasis mine. Well, that certainly illustrates the value of intuition vs. quantitative modeling (at least my intuition). Is there any Huygens data on droplet size?

-RD

-edit to make it more clear that I was wrong.