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Kepler-62: A five-planet system with planets of 1.4 and 1.6 Earth radii in the Habitable Zone

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 نشر من قبل Eric Agol
 تاريخ النشر 2013
  مجال البحث فيزياء
والبحث باللغة English
 تأليف W. J. Borucki




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We present the detection of five planets -- Kepler-62b, c, d, e, and f -- of size 1.31, 0.54, 1.95, 1.61 and 1.41 Earth radii, orbiting a K2V star at periods of 5.7, 12.4, 18.2, 122.4 and 267.3 days, respectively. The outermost planets (Kepler-62e & -62f) are super-Earth-size (1.25 < planet radius/earth radius < 2.0) planets in the habitable zone (HZ) of their host star, receiving 1.2 +- 0.2 and 0.41 +- 0.05 times the solar flux at Earths orbit. Theoretical models of Kepler-62e and -62f for a stellar age of ~7 Gyr suggest that both planets could be solid: either with a rocky composition or composed of mostly solid water in their bulk.



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