Viewing a single comment thread. View all comments

JimiWanShinobi t1_ixq4e6v wrote

Phobos and Deimos aren't really moons tho, neither of them are large enough for gravity to self correct their shape into a sphere. They're really just asteroids that got caught in Mars gravity and started orbiting instead of falling immediately to the surface...

−2

Wooden_Ad_3096 t1_ixqf1wx wrote

You’re mistaking the definition of a moon for the definition of a planet.

Moons don’t need a specific shape, planets do.

11

JimiWanShinobi t1_ixqgclv wrote

If that's the case then the James Webb telescope is a moon of Earth. You're mistaking the definition of a moon for the definition of a satellite, one of these two terms needs to be eliminated...

Edit: alright fine, I picked a bad example because I wasn't fully aware of where it's located. Surely there's better examples, like the International Space Station, nobody is calling that a moon either, it's still a satellite. If an asteroid flew by and got caught in the exact same position and orbital path it would still be a satellite, it wouldn't suddenly become The Moon 2...

−6

wgp3 t1_ixqh1ql wrote

Pretty sure naturally occurs versus man-made is probably a sufficient line to draw. Not to mention jwst doesn't orbit the earth. It orbits a Lagrange point between the earth and the sun. Which makes it in a heliocentric orbit rather than earth orbit.

5

Abuses-Commas t1_ixqj6by wrote

James Webb isn't in orbit around Earth, it's orbiting the Sun

2

peterabbit456 OP t1_ixrjq8z wrote

There is no requirement for moons to be spherical. See Saturn's smaller moons, including Hyperion.

I said something similar over at /r/asteroid about a year ago, about them being captured asteroids, and got refuted by a post-doc who knows more about the Martian moons than I. Now I'm not totally convinced, either way.

Personally, I think we will know a lot more after the JAXA probe brings back samples.

1