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I have a star system of large red dwarf around 50% of sun's mass, which has gas giant or ice giant orbiting in the habitable zone. The gas(ice) giant has terrestrial like moon which is habitable. That means that humans could live on it without technology.

Is my system possible?

I'm not attached to anything about the mass of the gas giant from Neptune to larger then Jupiter. Nor about the the type of the terrestrial planet as long as it's surface gravity is similar to Earth's.


marked as duplicate by Renan, Mołot, StephenG, Bellerophon, Community Jan 19 '18 at 14:12

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    $\begingroup$ By "terrestrial like planet" you mean "terrestrial like moon"? $\endgroup$ – Raditz_35 Jan 19 '18 at 11:27
  • $\begingroup$ @Raditz_35 Yes something Earth-ish. $\endgroup$ – Jiguna Jan 19 '18 at 11:29
  • $\begingroup$ @Jiguna Do you mean possible by gravity laws? Or in what sense of possible are you looking for an answer? $\endgroup$ – Legisey Jan 19 '18 at 12:12
  • $\begingroup$ @Legisey Yes. could I place them in such configuration that gas giant orbits the red dwarf in the habitable zone while terrestrial moon orbits the gas giant. $\endgroup$ – Jiguna Jan 19 '18 at 12:29
  • $\begingroup$ There are too many variables to take into account to say either yes or no. Radiation, flares, more pressure on flora due to light from star, impact of gravity tides on tectonism, period of moon orbit around the planet, and the period of the planet itself, presence or absence of rings... $\endgroup$ – Renan Jan 19 '18 at 12:43

Radiation is going to be your biggest hazard to habitability, both from the gas giant’s radiation belts and from flares on the red dwarf. Your planet needs to be quite far out from the gas giant, which is unlikely but not impossible, and you need to allow for frequent solar flares. Your inhabitants may be happier underground or under water.

  • $\begingroup$ As far as I know only Jupiter has dangerous radiation belts, what about something like Neptune? $\endgroup$ – Jiguna Jan 19 '18 at 12:21
  • $\begingroup$ Saturn does not have dangerous radiation at the distance of its larger moons, so radiation doesn't have to be a hazard unless the OP wants it to be. $\endgroup$ – kingledion Jan 19 '18 at 13:32

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