4 ms·

Any notion of why the Earth has only one moon and other planets have hundreds?

frabert 7y ago
The Earth is miniscule in comparison to the planets that have hundreds of moons. Those just have a stronger gravity field
- Yajirobe 7y ago
  What about Mars?
  - ehnto 7y ago
    It only has two moons, one more than earth for sure but nothing compared to the more massive planets.
  - Sebb767 7y ago
    Mars has even less mass than earth (5.972 × 10²⁴ kg vs 6.417 × 10²³ kg)
  - dragonwriter 7y ago
    Mars has two itty-bitty moons, and the other two terrestrial planets have zero moons. Earth’s moon has something like 99.99998% of the mass of all moons of terrestrial planets.
  - magduf 7y ago
    The "moons" of Mars are really nothing more than asteroids; they're a tiny fraction of the size of our Moon, and not even large enough to be round.
dmead 7y ago
yea. https://en.wikipedia.org/wiki/Circumstellar_habitable_zone https://en.wikipedia.org/wiki/Circumstellar_habitable_zone my understanding is that a good feature of the goldilocks zone is that it has fewer small objects than the outer planets region. maybe someone with better knowledge can pipe up.
Someone 7y ago
The earth is small and the moon relatively large (diameter 27% of that of earth; next is Triton, at 5%; volume-wise, the difference is even larger), so I guess the moon caught a lot of candidates. They may have more moons, but we likely have more moon, by mass, relatively. And does it? https://en.wikipedia.org/wiki/Claimed_moons_of_Earth#Modern_status https://en.wikipedia.org/wiki/Claimed_moons_of_Earth#Modern_...)
dragonwriter 7y ago
Of the four terrestrial planets, two have no moons, one has two tiny moons, and one (Earth) has a large moon. The jovian planets have lots of moons, but they are giant planets. The question is more “why does Earth have a big moon” than “why doesn't Earth have a slew of moons like a jovian planet.”
magduf 7y ago
The Earth has more than one moon. There are surely a bunch of very small rocks orbiting the Earth which we haven't discovered yet. And there was one other known moon of Earth, called 2006 RH120, in the last decade, but it was ejected.

The Earth is miniscule in comparison to the planets that have hundreds of moons. Those just have a stronger gravity field

Yajirobe 7y ago
What about Mars?
- ehnto 7y ago
  It only has two moons, one more than earth for sure but nothing compared to the more massive planets.
- Sebb767 7y ago
  Mars has even less mass than earth (5.972 × 10²⁴ kg vs 6.417 × 10²³ kg)
- dragonwriter 7y ago
  Mars has two itty-bitty moons, and the other two terrestrial planets have zero moons. Earth’s moon has something like 99.99998% of the mass of all moons of terrestrial planets.
- magduf 7y ago
  The "moons" of Mars are really nothing more than asteroids; they're a tiny fraction of the size of our Moon, and not even large enough to be round.

dmead 7y ago

yea. https://en.wikipedia.org/wiki/Circumstellar_habitable_zone https://en.wikipedia.org/wiki/Circumstellar_habitable_zone my understanding is that a good feature of the goldilocks zone is that it has fewer small objects than the outer planets region. maybe someone with better knowledge can pipe up.

Someone 7y ago

The earth is small and the moon relatively large (diameter 27% of that of earth; next is Triton, at 5%; volume-wise, the difference is even larger), so I guess the moon caught a lot of candidates. They may have more moons, but we likely have more moon, by mass, relatively. And does it? https://en.wikipedia.org/wiki/Claimed_moons_of_Earth#Modern_status https://en.wikipedia.org/wiki/Claimed_moons_of_Earth#Modern_...)

dragonwriter 7y ago

Of the four terrestrial planets, two have no moons, one has two tiny moons, and one (Earth) has a large moon. The jovian planets have lots of moons, but they are giant planets. The question is more “why does Earth have a big moon” than “why doesn't Earth have a slew of moons like a jovian planet.”

magduf 7y ago

The Earth has more than one moon. There are surely a bunch of very small rocks orbiting the Earth which we haven't discovered yet. And there was one other known moon of Earth, called 2006 RH120, in the last decade, but it was ejected.