Satellite Time Dilation Earth

The special theory of relativity predicts time dilation.

Satellite time dilation earth. For example at the iss time goes slower lagging approximately 0 01 seconds behind for every 12 earth months passed. If not kept in check the satellites would basically travel to the future technically. The global navigation satellite system is possible because of relativity. Begingroup there are actually two effects at play here.

Time dilation explains why two working clocks will report different times after different accelerations. 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. Let s focus on navigational satellites popularly but incorrectly referred to as gps.

However since the earth s gravitational pull is much stronge. 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. But for a gps another form of time dilation is also in effect because the fact that the satellite is in motion. The net effect is that the satellite clock is actually faster by 38 microseconds per day.

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. For gps satellites to work they must adjust for similar bending of spacetime to coordinate properly with systems on earth.