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Carbon Dioxide and Water Found On Exoplanet
Off the Rails writes "The BBC reports that evidence has been found for both water vapour and carbon dioxide on a planet 63 light years away. The planet is a 'hot Jupiter' with a surface temperature of 1173K and an orbital period of just 53 hours. The gases were found spectroscopically once its orbit had been deduced from observation. NASA hailed the news as proof that Kepler will be able to do its job of finding planets capable of supporting life." Wikipedia also has an entry on the planet, dubbed HD 189733b.
1175 K = 902 C = 1655.6 F
Really damn hot.
"That's LORD Kelvin to you!" - Adam Savage
Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
No, I guess I foolishly assumed it was a spelling error. Then I googled it. Slashdot has the 3rd result (as of now). There's no wikipedia entry. Googling "doxide definition" gives no relevant results. Please, enlighten me on this definition. It appears you are in the know on this obscure term.
My preferred name is frazz, but someone keeps taking it. If you see him, tell him I said hi.
NASA hailed the news as proof that Kepler will be able to do its job of finding planets capable of supporting life.
I guess all you need to support life these days is water vapor and carbon dioxide. Never mind that the planet is hotter than the surface of some stars.
I'm of the opinion that spending billions of dollars on searching for ET life is silly, but in this article's [or the summary thereof] defense, it didn't say THIS planet was habitable. My reading was that they simply proved (presumably) that they were able to find out if water and CO2 exists on a planet.
Kepler will be a small telescope (about 1 meter) in orbit, with the sole mission of looking at a few fixed areas on the sky and searching for planets by the transit method: take thousands of pictures and look for stars which become dimmer for a few hours due to a planet crossing their disks. This small mission will launch in spring 2009 and is NOT a replacement for HST.
The James Webb Space Telescope (JWST) is Hubble's replacement. It will be much larger (with a mirror around 6.5 meters in diameter) and carry out many, many different types of observations. This mission will launch, uh, some time around 2013, if all goes well.
Michael Richmond "This is the heart that broke my finger."
mwrsps@rit.edu http://stupendous.rit.edu
Carbon dioxide, on the other hand, is a surprise: at the temperatures and pressures encountered in an exoplanet atmosphere of this type, all carbon should be present as methane (if cool enough) or carbon monoxide. Giant planet atmospheres are generally far too hydrogen-rich for CO2 to form in any appreciable quantity. So its detection requires an extra-ordinary explanation for its origin.
Here is a Nature preprint from the same research group, describing H2O, CH4, and CO detection. I was hoping to find a research article (and not just a news story or press release) describing CO2 detection, but haven't found any yet...
Your understanding is incorrect.
Kepler is designed to detect planets that transit their parent stars. That is, the planet passes directly in front of the star from our point of view. That causes the perceived brightness of the start to decrease a little when the planet passes in front.
Kepler is expected to be able to detect Earth-sized planets. Since the planet passes directly in front of the star, you can measure changes in the spectra from the system as the planet passes in front. By subtracting the star - planet and the star + planet measurements, you can get an idea of the composition of the planet's atmosphere.