Question: Can mass effect time? If yes how?

Liza Sazonova answered on 11 Nov 2020:

Yup, and it does it all the time! The way it works is described by the Theory of General Relativity that Einstein came up with. It’s really hard to wrap your head around even for me, but the gist of it is that time /slows down/ near massive things. The more massive something is, the slower the time goes.
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It happens around you too but the effect is very tiny. The Earth, however, is big enough to make it noticeable! Time flows a little fast in space near satellites than it does on Earth. Satellites used for GPS navigation actually have to account for this to work correctly!