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First Exoplanet Atmospheres Analyzed

Posted by samzenpus on from the the-smell-of-exoplanets-in-the-morning dept.

deblau writes "NASA's Spitzer Space Telescope has captured for the first time enough light from planets outside our solar system, known as exoplanets, to identify signatures of individual molecules in their atmospheres. The landmark achievement is a significant step toward being able to detect possible life on rocky exoplanets and comes years before astronomers had anticipated."

5 of 106 comments (clear)

  1. EPA by Tablizer · · Score: 5, Funny

    Shit! They are all polluted also.

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    Table-ized A.I.
  2. Alien Infiltration? by Anonymous Coward · · Score: 5, Funny

    "The theorists' heads were spinning when they saw the data," said Dr. Jeremy Richardson of NASA's Goddard Space Flight Center, Greenbelt, Md.
    Better have some xenobiologists check those guys out. Or a priest.
  3. Subtraction works by Tablizer · · Score: 5, Interesting

    I think it is amazing how they can get the spectrum of the planet by substracting the spectrums of both using a formula like:

        planet = (star + planet) - star

    In other words, take the spectrum of both and compare it to the spectrum of the star when the planet is behind the star.

    It seems to me the star's spectra would be so strong as to wash out anything from the planet. However, maybe the specific chemical signatures they are looking for are weak in the star. For example, stars are probably too hot for a water line. Water would probably be converted into fundimental elements by the star.

    --
    Table-ized A.I.
  4. Re:Not earth like by 1fitz2many · · Score: 5, Interesting

    There have been some recent discoveries of some "super-Earth" planets, e.g. GJ 876d and a planet found through gravitational microlensing, that have masses several times that of Earth. In the core-accretion scenario for planet formation, it's hard to stop runaway gas accretion once it gets going, suggesting that such low-mass planets are rocky and not gaseous. Perhaps they're the remnant cores of former gas giants that have lost their gaseous envelopes via some process that occurred after formation.

  5. Re:So Our First Sign of Extraterrestrial Civilizat by David+Jao · · Score: 5, Interesting

    I think we'd be more amazed to discover a planet with an ozone layer, period.

    This is more true than probably most slashdotters realize. Ozone is the only chemical indicator of life that we can reliably detect across long distances.

    Ozone, unlike oxygen itself, has a strong absorption spectrum in the infrared wavelengths. A space-based infrared telescope (like Spitzer, but better) is exactly the right tool for detecting the presence of ozone. (A ground based telescope will not do, since infrared is absorbed by the atmosphere.) Finding ozone on a planet is just like finding oxygen -- the two compounds are so closely related that you can't have one without the other. And oxygen is a very volatile compound that reacts with almost anything else if you leave it alone. The only way for a planet to have free floating oxygen is if something on the planet is producing it.

    As far as we know, the only way to sustain an oxygen atmosphere on a planetary scale is with life. So, yes, finding ozone on a distant planet would be a very exciting discovery indeed.