The GPS satellites in stationary orbit around the earth have clocks that run a little faster than the clocks on the surface of the earth. This is predicted in Einstein’s GTR.(adsbygoogle = window.adsbygoogle || []).push({});

Because of this the satellite clocks have to be synchronised on a regular basis with those on the earth.

Assuming that the speed of light is constant regardless of the strength of the gravitational field. Can I assume this?

And for the sake of argument let the satellite clock run 10% faster than the clocks on earth.

If the satellite measures the time taken for light to go between two points on the earth, it will measure the time as 10% bigger than earth based observers.

Because distances are all effectively defined by the speed of light does the earth then seem 10% bigger from the satellite?

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# Time dilation and distances

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