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First water plume seen firing from Jupiter moon Europa

newscientist.com

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Re: First water plume seen firing from Jupiter moon Europa

#21

Post by yongjik »

deletes wrote: post #19
mturmon wrote: post #18

Earlier quoted context omitted.

Hmm. I did not think that the temperature of Europa's oceans (below their probable icy crust) has been well-constrained. To the extent that it has, I think the subsurface temperature is expected to be much greater than -50C in many places (the mechanism is tidal heating). There is a general belief that Europa is likely to have significant liquid water below its icy surface. The phase diagram for water (first image at…

Not really. https://www.youtube.com/watch?v=Fot3m7kyLn4 Also. http://en.wikipedia.org/wiki/Supercooling

From your link: A liquid below its standard freezing point will crystallize in the presence of a seed crystal or nucleus around which a crystal structure can form creating a solid.

Europa's ocean is surrounded by a vast sheet of actual ice. You can't keep such an ocean at supercooled state.

Re: First water plume seen firing from Jupiter moon Europa

#22

Post by Thrymr »

deletes wrote: post #19
mturmon wrote: post #18

Earlier quoted context omitted.

Hmm. I did not think that the temperature of Europa's oceans (below their probable icy crust) has been well-constrained. To the extent that it has, I think the subsurface temperature is expected to be much greater than -50C in many places (the mechanism is tidal heating). There is a general belief that Europa is likely to have significant liquid water below its icy surface. The phase diagram for water (first image at…

Not really. https://www.youtube.com/watch?v=Fot3m7kyLn4 Also. http://en.wikipedia.org/wiki/Supercooling

It's not likely that an entire large planetary body will maintain a state out of equilibrium for geological periods of time. Supercooling is unstable.

Re: First water plume seen firing from Jupiter moon Europa

#23

Post by [deleted] »

yongjik wrote: post #21
deletes wrote: post #19

Earlier quoted context omitted.

Not really. https://www.youtube.com/watch?v=Fot3m7kyLn4 Also. http://en.wikipedia.org/wiki/Supercooling

From your link: A liquid below its standard freezing point will crystallize in the presence of a seed crystal or nucleus around which a crystal structure can form creating a solid. Europa's ocean is surrounded by a vast sheet of actual ice. You can't keep such an ocean at supercooled state.

[deleted]

Re: First water plume seen firing from Jupiter moon Europa

#24

Post by [deleted] »

Thrymr wrote: post #22
deletes wrote: post #19

Earlier quoted context omitted.

Not really. https://www.youtube.com/watch?v=Fot3m7kyLn4 Also. http://en.wikipedia.org/wiki/Supercooling

It's not likely that an entire large planetary body will maintain a state out of equilibrium for geological periods of time. Supercooling is unstable.

[deleted]

Re: First water plume seen firing from Jupiter moon Europa

#25

Post by ep103 »

maaku wrote: post #14
stephth wrote: post #5

Please forgive my ignorance. What makes Europa more likely to contain life than other moons thought to contain oceans like Callisto, Ganymede, Titan, Enceladus ... ? [1] [1] http://img.gawkerassets.com/img/18lqil4sqeremjpg/original.jp... [2] [2] http://io9.com/5827649/a-map-of-all-the-water-in-the-solar-s...

Enormous oceans of liquid water, with internal tidal heat and protection from harsh surface environment?

And lets not forget the large black monolith.

Re: First water plume seen firing from Jupiter moon Europa

#26

Post by ceejayoz »

maaku wrote: post #13
jmpe wrote: post #8

This is an awesome phenomenon. Yesterday we had a post re panspermia: https://news.ycombinator.com/item?id=6888412 Now think of an Europa with simple bacteria living in the water under the ice. These events are like cosmic sporulation: long strings of frozen droplets that could contain organisms, ejaculated into space like spores in the wind.

And promptly sterilized. Unfortunately most plausible life forms require meters of soil/rock surrounding them to survive the harsh space environment (probably more in the vicinity of Jupiter).

We're finding extremophiles in all sorts of places we didn't expect. Radiation-resistant bacterial spores are hardly outside the realm of possibility - we've already found some.

Re: First water plume seen firing from Jupiter moon Europa

#27

Post by ceejayoz »

deletes wrote: post #10
trekky1700 wrote: post #7

Earlier quoted context omitted.

Doesn't water freeze and become ice at 0°C?

You can make supercooled water in your freezer. http://en.wikipedia.org/wiki/Supercooling

> The process of supercooling requires that water be pure and free of nucleation sites

Good luck finding distilled water with no contact with rocks/ice on Europa...

Re: First water plume seen firing from Jupiter moon Europa

#28

Post by trekky1700 »

deletes wrote: post #10
trekky1700 wrote: post #7

Earlier quoted context omitted.

Doesn't water freeze and become ice at 0°C?

You can make supercooled water in your freezer. http://en.wikipedia.org/wiki/Supercooling

That requires very difficult circumstances that almost certainly can't occur at the planetary scale.
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