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Astronomers Confirm a Hot and Steamy Exoplanet
The Bad Astronomer writes "The extrasolar planet GJ 1214b was discovered in 2009 orbiting a nearby (40 light year distant) red dwarf star. The planet was quickly found to have a thick atmosphere, but it wasn't known at the time if the composition was water vapor or a hazy shroud of particulates. New Hubble observations confirm the atmosphere of the exoplanet is rich in water, comprising up to 50% of the atmosphere's mass (PDF). At 230 degrees Celsius, this means the planet is shrouded in steam."
was a hot and steamy exoplanet.
I wonder what the water temperature at this planet's poles are
Actually, they do nothing of the sort. They just make water a more probable explanation for the observations. It says as much in the article.
These abstracts both state that the data indicates an atmosphere high in hydrogen and helium, but (taken from the second abstract):
Standing on what little land exists here, you watch a giant red dwarf sink slowly into the horizon of a hot ocean.
What a coincidence ... I was at the same party. That sunburned dwarf was pissed when they finally fished him out of the water.
Even if it doesn't spiral into the star the UV will be slowly splitting the water into its component parts and the hydrogen will disappear off into space. What happens to the O2 after that is anyones guess - perhaps it'll react with whatever rock is there or perhaps it'll end up as a huge oxygen atmosphere.
With green, topless alien women seducing plucky Canadian starship captains........
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
"The red, vain soul with a high degree of vertical challenge ever so slowly slipped out of sight past the horizon, less like a setting Sun than a discovered pervert shying away from sight with the slow shuffle that only stars can make look graceful in bathrobes, his red."
"Stratigraphically the origin of agriculture and thermonuclear destruction will appear essentially simultaneous" -- Lee
With a density of 2 gm /cc, this is likely to be a true water world - a world where a rocky interior is surrounded by thousands of miles of ice (not "our" ice, but Ice XI, X, VII), probably a few 100 km of hot liquid (kept from boiling by pressure), and then a steam bath. Look at this phase diagram, and remember that you are starting at 500 K or so, and the pressure increases greatly at depth, so going down into the planet means you are probably following a nearly vertical (but tilted to the right) line on the phase diagram.
Cool picture, but true water worlds are unlikely to have any true land (i.e., rocks at the surface). What they may have are mats of carbon materials too light to sink. On water worlds with biology, creatures may evolve to form such mats in symbiosis with air breathing animals (i.e., giving them a place to live, in return for goodies like nitrogen fixation from the atmosphere in their excretions), in much the same way as corals (the creatures that build coral reefs) get up to 90% of their nutrients from their symbionts.
Now, that would be a water world Kevin Costner could be proud of.