Do all planets have moons?

If the definition of planet is simply a body orbiting a star of (an arbitrarily picked) number of kilometers in diameter that has pulled itself into a sphere or spheroid, than yes, Pluto and the other minor planets that share it's designation (plutino) would qualify as planets. Because the International Astronomical Community desided to include this 'cleared it's orbit'(presumably of similarly sized objects) phraseology in it's 'accepted definition' of planet, than Pluto, which crosses the orbit of Neptune, falls short of qualifying.

I have a feeling the International Astronomical Community is going to eventually revisit this issue, it's just a question of when.

paige wrote:

why can we see only one side of the moon

Well Page or Kerry, the simple reason we only see one side of the Moon is because the Moon makes one complete spin(revolution) around itself, at the same time that it makes one complete orbit around our planet, thereby; keeping one side of it(the Moon) facing us(the Earth) at all times... simple enough?

freddy bobbins wrote:

Do all gas planets have rings?????????

no only uranus and saturn.

sdx bfncfl wrote:

<quoted text>
no only uranus and saturn.

Jupiter and Neptune have rings, so yes, all the gas giants (Jupiter an Saturn) and ice giants (Uranus and Neptune) in this solar system have rings.

It might be that all gas giants (extrasolar) have at least a little bit of a ring structure if only in the left overs from planetary formation -- material caught within the Roche limit of tidal shearing. I wouldn't be surprised about this.

I think the planets are so cool

I think the stars are even cooler.. not literally of course:)

0 Moons:
Mercury
Venus
Ceres
Makemake

1 Moon:
Earth
Eris

2 Moons:
Mars
Haumea

4 Moons:
Pluto

13 Moons:
Neptune

27 Moons:
Uranus

63 Moons and Over 150 Moonlets:
Saturn

66 Moons:
Jupiter

148 messages to answer the simple answer - no :)