Special relativity states that a fast moving object experiences time dilation – its clocks slow down relative to a stationary observer.
For more fun: A less known fact is that SR also states that from the POV of the satellite, the satellite is a stationary observer and the guy on earth is fast moving, therefore that observer's clock slows down relative to the satellite.
Yes, that's right: Each of them sees the other one's clock as slower.
IIRC It takes the fact that the satellite moves in an orbit, not in a straight line, to resolve which one is actually "slower" because up until then, the word "slower" isn't really meaningful at all.
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For more fun: A less known fact is that SR also states that from the POV of the satellite, the satellite is a stationary observer and the guy on earth is fast moving, therefore that observer's clock slows down relative to the satellite.
Yes, that's right: Each of them sees the other one's clock as slower.
IIRC It takes the fact that the satellite moves in an orbit, not in a straight line, to resolve which one is actually "slower" because up until then, the word "slower" isn't really meaningful at all.