Can moons have moons?
https://science.slashdot.org/story/18/10/11/2038243/moons-can-have-their-own-moons-and-they-could-be-called-moonmoons?utm_source=rss1.0mainlinkanon&utm_medium=feed
https://www.atlasobscura.com/articles/can-moons-have-moons
https://arxiv.org/pdf/1810.03304.pdf
moomoons ?
moonets ?
Rocks
Ian said:
Rocks
Sub rocks ?
I wonder how long term its orbit would be and would their be a size limit and I suppose depending on the size of them they orbit a common barycenter instead of one orbiting the other
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
dv said:
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
Planetary gravity getting in the way ?
dv said:
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
That’s not what they’re saying:
>Even our own moon is the right size and distance from Earth to potentially host its very own moon.
https://www.smithsonianmag.com/smart-news/earths-moon-could-host-moonmoon-if-moonmoons-are-thing-180970520/
Cymek said:
I wonder how long term its orbit would be and would their be a size limit and I suppose depending on the size of them they orbit a common barycenter instead of one orbiting the other
It’s been known for ages that moons can have moons, provided the second moon is inside the Hill sphere of the first moon. That means that it must be much closer in to the first moon than that moon is to its planet.
https://en.m.wikipedia.org/wiki/Hill_sphere
For example, our Moon orbits within the Hill sphere of Earth.
Actually, thinking on it, another necessity is that the density of the first moon must be nearly uniform around its circumference, or density variations will cause the orbit of the second moon to rapidly become more elliptical and crash. That means that the first moon must be bigger than asteroid Vesta, with a diameter of 525 km.
Bubblecar said:
dv said:
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
That’s not what they’re saying:
>Even our own moon is the right size and distance from Earth to potentially host its very own moon.
https://www.smithsonianmag.com/smart-news/earths-moon-could-host-moonmoon-if-moonmoons-are-thing-180970520/
Look, you are you going to trust, some wally associated with the Smithsonian Institution or our very own dv.
Cymek said:
dv said:
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
Planetary gravity getting in the way ?
For Io, yeah.
Bit different for the Moon. If it had its current mass and diameter but were spherical with a symmetrical mass distribution, it should theoretically be able to have moons. But it’s not: it is peppered with “mascons” (mass concentrations).
mollwollfumble said:
Cymek said:
I wonder how long term its orbit would be and would their be a size limit and I suppose depending on the size of them they orbit a common barycenter instead of one orbiting the other
It’s been known for ages that moons can have moons, provided the second moon is inside the Hill sphere of the first moon. That means that it must be much closer in to the first moon than that moon is to its planet.
https://en.m.wikipedia.org/wiki/Hill_sphere
For example, our Moon orbits within the Hill sphere of Earth.
Actually, thinking on it, another necessity is that the density of the first moon must be nearly uniform around its circumference, or density variations will cause the orbit of the second moon to rapidly become more elliptical and crash. That means that the first moon must be bigger than asteroid Vesta, with a diameter of 525 km.
So if moons in our system had moons and they didn’t fit the above then long ago they would have crashed
sibeen said:
Bubblecar said:
dv said:
Note that not all moons can have moons. The Moon for instance cannot have moons. Io cannot have moons.
That’s not what they’re saying:
>Even our own moon is the right size and distance from Earth to potentially host its very own moon.
https://www.smithsonianmag.com/smart-news/earths-moon-could-host-moonmoon-if-moonmoons-are-thing-180970520/
Look, you are you going to trust, some wally associated with the Smithsonian Institution or our very own dv.
Taking their statement literally, they are correct. It is indeed the right size and distance from the Earth to host its own moon.
The size and distance ain’t the problem…
https://www.space.com/21364-moon-gravity-mascons-mystery.html
Tau.Neutrino said:
Can moons have moons?https://science.slashdot.org/story/18/10/11/2038243/moons-can-have-their-own-moons-and-they-could-be-called-moonmoons?utm_source=rss1.0mainlinkanon&utm_medium=feed
https://www.atlasobscura.com/articles/can-moons-have-moons
https://arxiv.org/pdf/1810.03304.pdf
moomoons ?
moonets ?
From arxiv link:
“We assume tidal Love numbers k2,moon = 0.25 and tidal quality factor Q = 100.”
That’s a bit cavalier. Our moon doesn’t have the same internal mass distribution as the moons of Jupiter or Saturn, for instance. Even the orbital inclination of orbhts around our own Moon has a big influence on how long before a satellite of it crashes.
dv said:
sibeen said:
Bubblecar said:That’s not what they’re saying:
>Even our own moon is the right size and distance from Earth to potentially host its very own moon.
https://www.smithsonianmag.com/smart-news/earths-moon-could-host-moonmoon-if-moonmoons-are-thing-180970520/
Look, you are you going to trust, some wally associated with the Smithsonian Institution or our very own dv.
Taking their statement literally, they are correct. It is indeed the right size and distance from the Earth to host its own moon.
The size and distance ain’t the problem…
https://www.space.com/21364-moon-gravity-mascons-mystery.html
It seems as though dv and I have been saying the exact same thing at the same time. Good on ya dv.
If the above it true could one lesser fat momma orbit another larger fat momma
Cymek said:
If the above it true could one lesser fat momma orbit another larger fat momma
Yo mamma so fat that when she jumps in the air she gets stuck.
Boris, give witty his handle back, there’s a good boy.
sibeen said:
Boris, give witty his handle back, there’s a good boy.
that’s really cruel, sibeen.
Astronomers Find First Evidence of Possible Moon Outside Our Solar System
Using NASA’s Hubble and Kepler space telescopes, astronomers have uncovered tantalizing evidence of what could be the first discovery of a moon orbiting a planet outside our solar system.
more…
mollwollfumble said:
dv said:
sibeen said:Look, you are you going to trust, some wally associated with the Smithsonian Institution or our very own dv.
Taking their statement literally, they are correct. It is indeed the right size and distance from the Earth to host its own moon.
The size and distance ain’t the problem…
https://www.space.com/21364-moon-gravity-mascons-mystery.html
It seems as though dv and I have been saying the exact same thing at the same time. Good on ya dv.
go team