Quote:
Originally Posted by classicman
Ok - I'm dense - whaaaaattt???????
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what he's saying is this:
picture 2 equal sized spheres orbiting each other. the center of mass is located at the middle of the space between them....the axis which they rotate around.
now, make one larger than the other. the center point moves toward the heavier sphere, because it's gravitational pull is stronger. At some point, that point is located inside the surface area of the larger sphere. That makes the large object a planet, and the other a moon. If that point was located 3 feet outside the surface of the earth, .....luna would be a sister planet, not a moon.
capice?