system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:The mass of the sun is about 1050 times greater than that of Jupiter. I weigh 140 pounds (64 kg) and an ant weighs about 5 mg (0.000005 kg). My mass is about 1,280,000 times greater than an ant's. Why isn't an ant rotating around me?
gpt
A couple of reasons. One is that as long as you and the ant are on Earth, the planet's mass is so much bigger than both of yours' that the ant is mostly just being pulled towards the Earth. (Technically, the ant is being pulled towards the Earth and you and everything else in the universe all at once, but at a VERY sharp angle towards the Earth.)

If you were in space with no other objects though, even then an ant wouldn't necessarily circle you. In order to orbit something, the ant needs speed -- something would have to push it with a very perfect force and direction to get it to go around you without a) flying away or b) crashing into you.

Picture kicking a football. When it goes up in the air, it falls back down in a big arc. (That's how anything would fall, from an ant, to a ball, to Jupiter.) If you were Superman and kicked the football really, really hard, it's possible that the arc would be so wide that it would be about the size of Earth, and the football would never actually touch the Earth, just continually fall and curve downward  while the Earth's surface also curves. That perfect equality between the curve of the earth and the arc of the object's fall is what allows orbits, and requires a lot of precision to set up. 

So an ant could circle you in space, but would have to be "falling" in a very specific way, and almost for sure be set up by deliberate action.