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How does gravitational time dilation affect the operation of GPS satellites?

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gravitational lens — gravity A galactic cluster, about five billion light-years away, produces a tremendous gravitational field that “bends” light around it. This lens produces multiple copies of a blue galaxy about twice as distant. Four images are visible in a circle surrounding the lens; a fifth is visible near the center of the picture, which was taken by the Hubble Space Telescope.

Gravitational time dilation significantly impacts the Global Positioning System (GPS), requiring precise relativistic corrections to maintain accuracy.12

According to the theory of general relativity, time runs slower for clocks located closer to a massive body, where the gravitational field is stronger. Because GPS satellites orbit high above Earth, they experience a weaker gravitational field than receivers on the planet's surface. Consequently, the atomic clocks on board these satellites tick slightly faster than identical clocks on the ground.34

If these relativistic effects were not accounted for, the timing discrepancies would lead to significant errors in calculating the distance between the satellite and the receiver, as GPS relies on the precise measurement of signal travel time multiplied by the speed of light. By incorporating these relativistic corrections, GPS technology can calculate positions on Earth to within a few centimeters.52