Let’s say aliens pay us a visit. They bring some of their ships. Think huge deathstar sized sphere’s, or maybe irregular shapes but still ¼ the size of our moon.

They send over a dozen of these. How close can they get before they mess up our gravity, oceans, spin-cycle?

Topics: science, astronomy, physics, Newton, chemistry, space, NASA, cosmology, moon, gravity, UFOs, satellites, Einstein, musk