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RE: Exoplanet moons
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Earth-sized moons may orbit around ''hot Jupiters''
In a new study, scientists have determined that giant gas planets like Jupiter, which orbit close to their parent star, could harbour moons the size of Earth.

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Exomoons
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Habitable moons 'could to be spotted by 2014'
British astronomers have claimed that thousands of moons capable of supporting life, like those shown in the popular Star Wars' flicks, could be scattered all over our galaxy, and are likely to be spotted by 2014.


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See also Kepler mission

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Exoplanet moons
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Title: Massive Satellites of Close-In Gas Giant Exoplanets
Authors: Timothy A. Cassidy, Rolando Mendez, Phil Arras, Robert E. Johnson, Michael F. Skrutskie

We study the orbits, tidal heating and mass loss from satellites around close-in gas giant exoplanets. The focus is on large satellites which are potentially observable by their transit signature. We argue that even Earth-size satellites around hot Jupiters may be immune to destruction by orbital decay; detection of such a massive satellite would strongly constrain theories of tidal dissipation in gas giants, in a manner complementary to orbital circularisation. The star's gravity induces significant periodic eccentricity in the satellite's orbit. The resulting tidal heating rates, per unit mass, are far in excess of Io's and dominate radioactive heating out to planet orbital periods of months for reasonable satellite tidal $Q$. Inside planet orbital periods of about a week, tidal heating can completely melt the satellite. Lastly, we compute an upper limit to the satellite mass loss rate due to thermal evaporation from the surface, valid if the satellite's atmosphere is thin and vapour pressure is negligible. Using this upper limit, we find that although rocky satellites around hot Jupiters with orbital periods less than a few days can be significantly evaporated in their lifetimes, detectable satellites suffer negligible mass loss at longer orbital periods.

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