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jhairehmyah t1_jc2igv9 wrote

It “rains” liquid methane on Saturn’s moon of Titan.

https://en.wikipedia.org/wiki/Climate_of_Titan

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DrSmirnoffe t1_jc2sdyt wrote

More intensely at the poles, since the equator's typically too hot for bodies of "methanum" (that's what Atlas Pro coined to refer to liquid methane). In fact, despite Titan being a very cold world, most of the surface isn't cold enough for methane to condense into a liquid state, so the poles are typically where you'll find lakes of methanum.

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puffic t1_jc3tjem wrote

I don’t think that’s correct as there’s very little difference in surface temperature between the poles and equator on Titan. It probably has more to do with Titan’s long seasons and it’s axial tilt. In any case there are equinoctial storms in Titan’s tropics, but the liquid methane seeps into the dry surface. There is some evidence that it flows back poleward within subsurface aquifers.

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NomenNescio13 t1_jc2rx4b wrote

That was my first thought as well, but I wonder—in the spirit of the question—wouldn't that just be rain?

(This is obviously for OP to answer, the rest of us can only guess as to their meaning.)

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Zondartul t1_jc2urj2 wrote

We distinguish rain, snow, slush and hail by the phas-of-matter and composition of the falling "water"... as alternatives to "falling" water, we have fog, dew, jack frost, icycles... different ways for water to arrive on something. We also have different end results: puddle, mud, snow, black ice.

Differentiating precipitation by the chemical that falls is easy (we have water, acid, ash, and fish here on earth) but I find the different physical processes of precipitation also interesting. For example, frozen CO2 (aka dry ice) sublimates into gas, and the opposite process (deposition?) would be interesting to see.

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aphilsphan t1_jc2znif wrote

CO2 deposition would occur at the Martian poles. The dry ice sublimes when the temperature gets high enough and deposits again when it gets colder. This drives a lot of the changes in atmospheric pressure.

I’d like to see a planet with enough pressure and the right temperature range for CO2 to be a liquid. I’m sure there are ammonia dominated planets.

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OlympusMons94 t1_jc3jq6v wrote

CO2 near Venus' surface is a supercritical fluid, which is neither gas nor liquid, but has properties of both. At present, the CO2 is more gas-like, but in the past Venus' surface pressure may have been even higher, possibly enough to support a more liquid-like supercritical CO2 (Bolmatov et al., 2014).

There is also supercritical CO2 within Earth's crust. Supercritical and even actual liquid CO2 are released by hydrothermal vents on the sea floor.

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zekromNLR t1_jchro7m wrote

If Venus were cooled to a sufficiently cold temperature (to achieve that, most of the sunlight that hits it would need to be blocked), most of its supercritical CO2 atmosphere would condense out into an ocean of liquid CO2, that would then freeze over into a crust of dry ice hundreds of meters thick.

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cheesynougats t1_jc5ib8l wrote

"water, acid, ash, and fish. "

Excuse me, what?

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Enorats t1_jc5nn4t wrote

Tornados occasionally suck up fish and can drop them many miles away in large quantities.

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