Satellite Time Dilation Earth

Begingroup there are actually two effects at play here.

Satellite time dilation earth.

Just a little slower. Since the satellite is moving faster than the earth for every day on earth the clock on the satellite shows one day minus 7 microseconds due to time dilation due to special relativity. This effect is only nanoseconds in size near the earth. It is possible to observe the combined effect of general and special relativity on an atomic clock on board a gps satellite.

If not kept in check the satellites would basically travel to the future technically. However since the earth s gravitational pull is much stronge. The global navigation satellite system is possible because of relativity. Let s focus on navigational satellites popularly but incorrectly referred to as gps.

But for a gps another form of time dilation is also in effect because the fact that the satellite is in motion. Time dilation explains why two working clocks will report different times after different accelerations. The net effect is that the satellite clock is actually faster by 38 microseconds per day. A clock on a fast flying satellite appears to run slower when observed from a stationary position on earth.

For example at the iss time goes slower lagging approximately 0 01 seconds behind for every 12 earth months passed. The special relativity induced time dilation due to the relative velocity of the satellite and the decrease in gravitationally induced time dilation described by general relativity due to the increased height above earth.