You don't need a human to bounce around the moon to know there is gravity. A robot kicking dust, all the rocks that you can see are all evidence of gravity. With a telescope, you can see other planets have moons too. so those planets have a gravitational pull.
You don't need a human to bounce around the moon to know there is gravity. A robot kicking dust, all the rocks that you can see are all evidence of gravity. With a telescope, you can see other planets have moons too. so those planets have a gravitational pull.