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Tom Mazanec
2012-Aug-13, 03:21 PM
What is the maximum number of moons or moonlets that a habitable planet could plausibly have? Define "moon" as opposed to "moonlet" as a natural satellite big enough for hydrostatic equilibrium, and a moonlet as being irregular, and habitable as being colonizable by humans.
Can a habitable planet have two moons? Three? Four? Can it have four moonlets? Six? Ten?

Noclevername
2012-Aug-13, 09:51 PM
From what I've been told, two large moons is unlikely and three is probably the practical limit.

As for moonlets, it might be possible to have a great many, as long as their orbit isn't interfered with by a large moon's tide. However, for small moonlets, the most likely method of acquisition is capture, so a planet with that many small bodies in orbit probably means it's in a region of many asteroids, and so its habitability may be in question.

WayneFrancis
2012-Aug-14, 12:49 AM
Are you talking an Earth like planet? We know Ceres is less then 1000km in diameter and is rocky. The number of moons you could have would be very dependant on the whole system's configuration. The issue I see is that to be close enough for liquid water you are probably going to be close enough where the system's sun will effect the orbits of multiple moons in such a way that they'll be less stable. If you use one of the few gravity simulators out there then you could test how stable your system was and for how long.

John Mendenhall
2012-Aug-14, 01:36 AM
What is the maximum number of moons or moonlets that a habitable planet could plausibly have? Define "moon" as opposed to "moonlet" as a natural satellite big enough for hydrostatic equilibrium, and a moonlet as being irregular, and habitable as being colonizable by humans.
Can a habitable planet have two moons? Three? Four? Can it have four moonlets? Six? Ten?

Hydro static equilibrium? What do you mean?

Noclevername
2012-Aug-14, 01:55 AM
Hydro static equilibrium? What do you mean?

A round ball. Molten rock found its level before cooling.