moving {Ans: The planets don't get pulled all the way into the Sun because they are _______________.}flying {Ans: If there were no gravity, all the planets would go ______________ into space.}round {Ans: Planets are ___________ because of gravity.}moon {Ans: When the astronaut on the _________ dropped the feather and the hammer, they hit the ground at the same time.}matter {Ans: Other planets in the solar system have a lot of ______________ and so they also have gravity.}down {Ans: No matter where you are on the surface of Earth _________ is the same way.}