Can moons have moons of their own?

[DavidSmafield]

Can moons have moons of their own or is that impossible ?

 

[MeteorWayne]

Welcome to Space.com.

No not impossible, but very unlikely that it would be stable. Most moons are very small in relation to their planet, and the gravitional interactions with the planet would rip it away.

A very large moon, a long way from it's planet, could conceivably have a moon of it's own, for a while anyway.

Wayne

 

[crazyeddie]

Can moons have moons of their own or is that impossible ?

Recall that our own moon first had artificial satellites of it's own back in the 1960's, the Russian Luna series and the American's Lunar Orbiter series. All of them eventually crashed onto the lunar surface, due to orbits that were continually degraded by the tidal tugs of Earth's gravitational influence. So yes, moons can have moons of their own, but they cannot hang on to them for very long.

 

[raptorborealis]

Can moons have moons of their own or is that impossible ?

There are quintillions times quintillions of solar systems in the universe. Probably 'gazillions' of moons with moons.

The permutations of possible of stars, binary stars, planets , moons etc, isn't infinite but just about every variation is possible.

Any solar system configuration in the universe that 'can exist' probably does when there are 10 to the 23rd power of stars. that's...1000000000000000000000000

 

[Couerl]

Any solar system configuration in the universe that 'can exist' probably does when there are 10 to the 23rd power of stars. that's...1000000000000000000000000

There's still more possible positions and combinations on a chess board than there are atoms in the universe but, the likelihood of ever arriving at each and every one of those positions due to general laws of the game make it unlikely and many of them will simply never surface. :geek:

 

[silylene]

Can moons have moons of their own or is that impossible ?

It is possible.

For example, 2001 QW322 is a highly split Kuiper Belt pair, orbiting a common center of mass at a distance of 125,000 km, and their gravitational attraction to one another is very slight, given their distance from each other, and their small mass. And their orbit within the solar system is quite stable, given their great distance from any planets. If one of the QW322 pair has a tiny undetected moon that is rather close in, I would suspect its orbit would be stable and not subject to any appreciable pertubation. About 25% of Kuiper asteroids have moons, so perhaps the chances that one of these two has a moon might be about 50%. In a sense, this would be the moon of a moon.
http://www.astroengine.com/?p=1976

 

[DavidSmafield]

Cool, thank for your answers

 

[3488]

On a similar'ish' sort of vein to the answer provided by silylene,

There is a possibility that some of the outlier moons of Jupiter, Saturn, Uranus & Neptune could also be close doubles or contact binaries. I am not sure & the only outlier moon seen in close up to date is the Saturn moon Phoebe, which appears to be a single solid coherent ice & rock body, most likely a captured KBO or Centaur by Saturn.

Recently Cassini spacecraft had searched for evidence of rings, either past or present in orbit around Rhea (Saturn's second largest moon), but the searches have drawn a blank, though it is not impossible for Rhea to have a tiny close in moon, though I think it's highly unlikely.

It is possible that Saturn moon Iapetus (Saturn's third largest moon) & Uranus moon Oberon (Uranus's second largest moon) could hold a small close in moon, as they are fairly large moons, long way out from their parent planets (Saturn & Uranus respectively). All four of the Jovian Galileans could, though once again there is no evidence of the existence of said bodies as can our own Moon (large body in it's own right quite a long way from Earth, thought the moon has MASs CONcentrations MASCONS that would deorbit a small moon & we know Jupiter moons Io & Ganymede do too).

It IS possible, though so far there is no evidence for the existence of moons orbiting moons.

Andrew Brown.

 

[silylene]

...There is a possibility that some of the outlier moons of Jupiter, Saturn, Uranus & Neptune could also be close doubles or contact binaries. I am not sure & the only outlier moon seen in close up to date is the Saturn moon Phoebe.....

Interesting notion, I hadn't thought of that!

 

[raptorborealis]

Any solar system configuration in the universe that 'can exist' probably does when there are 10 to the 23rd power of stars. that's...1000000000000000000000000

There's still more possible positions and combinations on a chess board than there are atoms in the universe but, the likelihood of ever arriving at each and every one of those positions due to general laws of the game make it unlikely and many of them will simply never surface. :geek:

Which means nothing (not to be disrespectful or dismissive). Your 'B' has no relation to my 'A'. One could add ten squares per chessboard side thus skyrocketing the move possibilites but it would and it neither add or detract from the physical properties of the Universe The physical properties of mass and energy are 'univefrsal'. The arrangement of solid bodies of matter leads us to believe that there are moons around other moons. Some Star, planet, moon configurations will lead to the formation of moons around moons....no need to play out every one of the 10 to the 23rd power possibilities. Physics tells us that at the macro level that all solar systems will not be unique from eachother.