(Okay, if you think you've seen this before, that's because this is a cross-post from the old forum
:
http://s1.zetaboards.com/The_Coffee_Hous...8011425/1/)
A while back, I was thinking about the way in which the Solar System is structured, with all these objects orbiting one another. "There are planets orbiting the Sun, and moons orbiting those planets....so, is it possible for anything to orbit those moons? And, if so, what would those 'moons of moons' be called?"
This prompted me to look a little further into this - upon which, I found the following short video by Fraser Cain, explaining that it would be pretty difficult, because gravity and tidal forces would probably pull the orbits apart:
However, he explains that it
may be possible if the objects were distant from one another. For example, in our own solar system, Neptune is the furthest planet from the Sun; it's conceivable in theory that it could have a distant moon with a 'moon' of its own. However, we haven't seen any sign of such a moon yet
.
(Well, at least....Neptune is the most distant
known planet from the Sun. If
Planet Nine exists, then perhaps it has one of these moons
? I have to admit, I kind of want it to!)
it can happen and im sure somewhere in just our galaxy there exists a moon with a moon. space is extremely vast and we should expect the unexpected.
Yeah, I'd be surprised if there weren't
any examples of it anywhere in the universe. If you had a star with a distant planet two or three times the size of Jupiter, which had a distant moon the size of Earth, then that moon could quite easily have its own 'moon'.
That kind of setup isn't particularly
likely, but it certainly wouldn't be impossible, and I expect there are at least one or two examples of it in the universe.
(Might be a while until we find them, though
)
That was a cool video and I enjoyed it.
(08-21-2018, 11:45 PM)Kyng Wrote: [ -> ]Yeah, I'd be surprised if there weren't any examples of it anywhere in the universe. If you had a star with a distant planet two or three times the size of Jupiter, which had a distant moon the size of Earth, then that moon could quite easily have its own 'moon'.
That kind of setup isn't particularly likely, but it certainly wouldn't be impossible, and I expect there are at least one or two examples of it in the universe.
(Might be a while until we find them, though )
perhaps when the replacement for Hubble is finally placed in orbit we may actually find some of these moons of moons?
(08-24-2018, 07:43 AM)GrieferLord Wrote: [ -> ] (08-21-2018, 11:45 PM)Kyng Wrote: [ -> ]Yeah, I'd be surprised if there weren't any examples of it anywhere in the universe. If you had a star with a distant planet two or three times the size of Jupiter, which had a distant moon the size of Earth, then that moon could quite easily have its own 'moon'.
That kind of setup isn't particularly likely, but it certainly wouldn't be impossible, and I expect there are at least one or two examples of it in the universe.
(Might be a while until we find them, though )
perhaps when the replacement for Hubble is finally placed in orbit we may actually find some of these moons of moons?
Quite possibly, although I would be surprised. The setup I described is very specific and likely to be vanishingly rare (if it even exists at all). Since we've only discovered 3,815 exoplanets (at time of writing), I'm not at all surprised that it hasn't occurred among these first 3,815.
Maybe once we've found a trillion or so exoplanets, I'll be surprised if we still have no "moons of moons", but I expect we'll need to wait a very long time for that
.
i suppose, though again, space is vast so there is more than likely at least a handful of these moons of moons even if we can not currently observe them.
Apparently, some scientists have run simulations, and they've determined that the concept
is plausible in theory:
https://www.sciencealert.com/can-a-moon-...n-moonmoon
However, they haven't yet agreed on what to call these things. Some are using the term 'submoons', but others are going with 'moonmoons'!
Another article on the same study, now that it's been through peer review:
https://earthsky.org/space/can-moons-hav...n-submoons
This second article raises another interesting possibility. Even though the Earth's moon doesn't have one of these 'sub-moons', it
could be possible for us to put an artificial one there, perhaps to serve as a 'Lunar Gateway' for other missions to Mars and beyond.
It's an interesting concept, but I have to ask how big it has to be before it can be classified as an 'artificial moon', and not merely a space station. I'll guess I'll need to re-watch the bit of
A New Hope where Luke Skywalker and Obi-Wan Kenobi debated that
.
considering if we go the SW route the deathstar was effectively the size of a moon yet was a space station i suppose it comes down to size and what its meant to do? perhaps an artificial creation would be a space station while something with terafirma and some gravity would be a sub moon?