I rewatched “Interstellar” and the time dilation dilemma makes my brain hurt. If a change in gravity alters time then wouldn’t you feel a difference entering/exiting said fake planet?

Question

I rewatched “Interstellar” and the time dilation dilemma makes my brain hurt. If a change in gravity alters time then wouldn’t you feel a difference entering/exiting said fake planet?

In: Planetary Science

Answer 1

If you like, I can make your head hurt more by noting that the way GPS works is by having very precise clocks on satellites orbiting the Earth. But because of the difference in gravity between the surface of the Earth, and the satellites in orbit, the clocks have to run more slowly (by about 38 microseconds per day) in order to properly synchronize with ground-based clocks to make the GPS system work. (Note that an error of 38 microseconds translates to *miles* of location error.)

[More information here.](https://www.astronomy.ohio-state.edu/pogge.1/Ast162/Unit5/gps)