Water found on distant planet (hot Jupiter at 63 LY)

[marcus]

Water found on distant planet
from PhysicsWeb News at 17:01 PM GMT
An international team of astronomers has obtained the first convincing evidence of water in the atmosphere of a planet outside our solar system. They came to this conclusion using NASA's Spitzer Space Telescope to measure the light absorbed by the Jupiter-like planet HD 189733b as it passed in front of its companion star. However, the planet, which lies some 63 light years from Earth, is unlikely to harbour life as its surface temperature can reach 1200K. (Nature 448 169).
July 11, 2007 17:01 PM GMT
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I guess part of the point is that absorption spectroscopy can now detect water in the atmosphere of exoplanets.

It is no surprise that water exists on some exoplanets, but it is nice that instruments can detect it.

Now if they would find water in the atmosphere of a planet in habitable zone that would be nice.

 

[Renge Ishyo]

What I want to know is, how is the water on such a planet prevented from boiling off? The normal boiling point for water on our planet is 373 degrees K, and this planet is apparently 4 times that hot...(I suppose an argument can be made for a higher atmospheric pressure on this panet but at this temp, that seems sort of unlikely to me...)

 

[mgb_phys]

When they say water - that includes water vapour.
The mass of a Jupiter like planet gives you a lot of gravity, certainly enough to hold onto an atmosphere,
our Jupiter is made of methane but that doesn't boil off.

 

[SpitfireAce]

thats so cool, thanks marcus =)
I personally find the technique they used even more interesting than the find itself

 

[marcus]

Ace, so glad you found it interesting! I agree about the cool use of spectroscopy.
I forgot to include some links:

http://www.planetary.org/news/2007/0711_Water_Found_on_Exoplanet.html

http://www.esa.int/esaCP/SEMBDZI2O3F_index_0.html

http://www.astronomy.com/asy/default.aspx?c=a&id=5783

 

[Renge Ishyo]

When they say water - that includes water vapour.
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I guess my mental image of streams of water being found was too optimistic