Earth-Like Gas Giant Moons
January 12, 2009 11:11 PM Subscribe
What would be the conditions required on the moon of a gas giant to support Earth life?
posted by Electrius to Science & Nature (17 answers total) 5 users marked this as a favorite
Let's say you have a moon of a gas giant in some fictional star system much like our own. If a spaceship from Earth came there, what would the parameters be if the settlers wanted to touch down and build some cities without being under domes?
My thoughts are that it would need to be a small gas giant, and the moon would have to orbit very close to it (since moons of gas giants seem to inevitably experience tidal lock, and you need to have days that are relatively in sync with Earth days, right?) but this would mean that only half the planet would receive sunlight and be habitable-- thereby making the rest into a featureless icescape, with a permanently crepuscular region between the two? Can I solve this by giving the moon a strong ecliptic tilt? Would this put the moon too close to form in the first place or too close to maintain its shape? Would it bathe the surface in too much radiation for life to exist? Would tidal forces turn it into a barren volcanic wasteland? If it had an orbit at something of an angle to the gas giant's orbit, would the problems be mostly resolved?
In addition to the parameters of its physical location, what kinds of unusual astronomical phenomena could inhabitants expect to see on the surface, if any?
I'm a Latin major who has only a casual and mostly science-fictional interest in astrophysics, and I only want a relatively vague idea. If you know of a book or article that basically answers this question, please point me to it. Google turned up some things but I want more and more complete answers, since of course this is kind of a bizarre subject and I doubt much concrete research has been done on it.