Page 2 - So... how many planets, again?

D1 and pyromonkey would never say the same thing said a blind clown in a cave...

Our moon won't be classified as a planet because it orbits US, not a star; the center of gravity between Earth and moon is actually within the Earth. However, the center of gravity between Pluto and Charon is actually not within either body, therefore they both orbit the sun. Or something like that.

I'm really disappointed that they're going to rename Xena. Especially since they named its moon Gabrielle. Now *that* will have to be changed too.

the two orbit each other, technically, and the center of orbit orbits the sun.

and our moons orbits are affected by the sun.

Actually, they don't orbit eachother....that's impossible for two adjacent objects to orbit eachother....

They orbit the space between them, while also orbitting the sun. Basically, they orbit the sun while in a flat spin with eachother, if that makes sense.

well, now I don't claim to know that much about physics, I DID get a D.

But would the two bodies cause a bend in space that isn't two smaller ones but one bigger one and they both just ride the outside of it, being pushed out by inertis and in by the other planet's gravity?

So they would orbit each other.

From a physics point of view, the mass from a large body, such as a planet, causes a gravitational pull on all other surrounding object. This gravitational pull forces the body to form an elliptical orbit around the larger body. The orbittal path is based on the gravity of the larger object and the centripetal force (mass of the smaller body and orbittal velocity). These two bodies in particular are too far away to be affected by the gravity of any other objects except the sun.

Well could you also think of it as a set of metal balls on a string, hooked to a rod that both spin around? The force keeping the balls in, here being the string, would be the force on it by the other body?

say what? lol

That's sort of a bad analogy because there is no rod. However, that is the motion that I was talking about. Imagine taking your rod and walking in a circle around the room. Now the balls would be taking a path similar to the orbit of pluto.

Well, I guess you are right that they are orbiting the space between them, but they are influenced by each other and they do rotate around each other. however, because each moves, the center of orbit for each planet moves, or to our vision it stays between them.

So they are orbiting each other around a point outside of both.

I think we're both trying to say a different explanation for the same thing.

Everything that has mass creates gravity and does effect to some degree all other objects.

also
disagree with-Quote These two bodies in particular are too far away to be affected by the gravity of any other objects except the sun.
The larger outer planets have a great effect, and have be known to change their orbit to a degree.

true, but, gravity only becomes a factor when the mass is much higher then the object it's having an effect on.

I forget the equation of the force on an object by an object due to gravity....


ggrrrr...I can see it written on that big ass blackboard.....this is the part of the class (at the end) that begun to spark my interest. Gravity and space and junk.

And does not the moon also effect the orbit of the earth around the sun. All the planets and moons effect each other AND the other planets orbits to some degree.

The moon does affect the orbit of the earth, but to a very small degree bc the moon is considerably less massive.

However, the moon affects the motion of water on this planet bc water is much less dense then the moon.

Also, thinking about it that way, the earth has an effect on the sun as well. But I can't count that many decimal points.

Must...get...mind...out...of...gutter...lol

I think it'll be good to have some concrete definitions.

A planet can be the size of the moon. We aren't the only planet in the solar system. Most planets in other galaxies that we are able to see with our telescopes are so huge that to them earth would be a small moon. I think mass and density would be a much better way to characterize a planet than size.