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The WASP-18b mystery

  1. Aug 29, 2009 #1
    Does someone know the mass of the mother star WASP-18b is circling around as well as the rotation speed?
  2. jcsd
  3. Aug 29, 2009 #2
    The only mass i could find for it was "roughly 10 times the mass of jupiter" from this article (http://www.skyandtelescope.com/news/55066637.html [Broken]).

    As for rotation speed, the only thing i saw is that it rotates inward and has an orbit time of around 22.5 hours.

    EDIT: oops. didn't see mother star. facts above are for WASP-18b, sorry.
    Last edited by a moderator: May 4, 2017
  4. Aug 29, 2009 #3


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    Given the period of WASP-18b, and its distance (~.02 AU), I come up with a mass for the star of 1.2 solar masses, which agrees with the articles which say that it is a sun-like star.
  5. Aug 29, 2009 #4
    I just hear 1.25 times that of the Sun, so Janus you are very close.
    And I hear one rotation: 5.6 days

    How can the tide effect on that planet be calculted?.
    (I have read that it is so strong what we expect the planet will be be 28 seconds faster in the next decade.)
  6. Aug 31, 2009 #5
    NASA does not list a star with exoplanets with the designation WASP-18:
    http://nsted.ipac.caltech.edu/index.html [Broken]

    Nor was there an exoplanet that came to light in 2006 with a mass of ten Jupiters.
    http://planetquest.jpl.nasa.gov/atlas/atlas_search.cfm?&Sort=DiscDate&SortDir=DESC [Broken]

    or that has the designation WASP-18b.
    So you have a story about an unknown exoplanet that orbits a star that doesn't exist.
    Maybe that is the mystery?
    Last edited by a moderator: May 4, 2017
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