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Kepler-9 b,c planets discovered

  1. Aug 27, 2010 #1


    On August 26, 2010, scientists announced the discovery of two planets orbiting around Kepler-9.

    Kepler-9 b - 0.252 MJ - 0.14 AU - 19.24 days
    Kepler-9 c - 0.171 MJ - 0.225 AU - 38.91 days

    http://en.wikipedia.org/wiki/Kepler-9" [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Aug 27, 2010 #2
    More details...


    NASA's Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star.

    The transit signatures of two distinct planets were seen in the data for the sun-like star designated Kepler-9. The planets were named Kepler-9b and 9c. The discovery incorporates seven months of observations of more than 156,000 stars as part of an ongoing search for Earth-sized planets outside our solar system. The findings will be published in Thursday's issue of the journal Science.


  4. Aug 27, 2010 #3


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    Cool find (though not exactly Earth-like. They're 500-1000x the mass of Earth.)
  5. Aug 27, 2010 #4


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  6. Aug 28, 2010 #5


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    Many exoplanets have masses several times that of Jupiter, but the Kepler planets are relatively small.

    "The observations show Kepler-9b is the larger of the two planets, and both have masses similar to but less than Saturn. Kepler-9b lies closest to the star with an orbit of about 19 days, while Kepler-9c has an orbit of about 38 days."

    Ref: http://www.nasa.gov/centers/ames/news/releases/2010/10-73AR.html

    Based on the masses 0.252 MJ and 0.171 MJ cited by Orion1 from Wikipedia, those are roughly 80 Mearth and 54 Mearth, respectively. Jupiter is about 318 Mearth.

    cf http://en.wikipedia.org/wiki/Jupiter_mass
    Last edited: Aug 28, 2010
  7. Aug 28, 2010 #6


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    Oh I know, I've been following them closely over the years with frequent visits to http://exoplanet.eu/catalog-all.php" [Broken].

    It's just that Kepler is a search for smaller planets.
    Last edited by a moderator: May 4, 2017
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