Originally Posted by RyuLion

First off, here?s the physics. Earth is not the only thing with gravity. The moon exerts a gravitational force on things, but it just exerts less force, mostly because it?s just got less stuff. Stuff attracts stuff, and so less stuff will attract other stuff less strongly. If you drop a pen, it will fall slowly, because the acceleration due to gravity is weaker. Earth is far away, but that doesn?t really matter ? when you are on the surface of the moon, the gravitational attraction of the moon is stronger than that of the earth. That?s why the astronauts could jump very high on the moon. You would weigh less on the moon than you do on the earth. If the astronauts jumped really really really hard, they could float away from the moon. The same is true on the earth (but to jump that hard, you need rockets, and that?s what the space shuttle does).

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Myth: The astronauts didn?t float away because they had heavy boots