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A comment on Two potentially life-friendly planets found orbiting a nearby star. Parent comment

Re:Two potentially life-friendly planets found orbiting a ne... by titzer on Tuesday June 18, 2019 @09:58AM (#20213010)
Such planets might also have moons.
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Re:Two potentially life-friendly planets found orbiting a ne... by bencollier49 on Tuesday June 18, 2019 @10:20AM (#20213269)
Not ones with 1.1g!
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Re:Two potentially life-friendly planets found orbiting a ne... by titzer on Tuesday June 18, 2019 @10:32AM (#20213443)
Why not?
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Re:Two potentially life-friendly planets found orbiting a ne... by Evidlo on Tuesday June 18, 2019 @10:40AM (#20213554)
Because then it would be a double planet.
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Re:Two potentially life-friendly planets found orbiting a ne... by titzer on Tuesday June 18, 2019 @10:56AM (#20213772)
It depends on how big the "main" planet is, I guess. But I think we are running into definitional issues here, and it gets technical very fast. First, IAU does not recognize the term "double planet". Second, a body which is large enough to reach hydrostatic equilibrium (i.e. a sphere) but has not yet cleared its orbit is technically not a planet. So I don't know where this leaves us. A Jupiter-sized planet with an Earth-sized satellite would be such a huge mass and volume difference (an even bigger difference than the Earth and Moon) that it seems to odd to term that a "double planet".
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Re:Two potentially life-friendly planets found orbiting a ne... by bencollier49 on Tuesday June 18, 2019 @02:20PM (#20216538)
TFA said the planets were rocky and 1.1g.
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