Fact #43
July 26, 2026Your GPS Depends on a Real Life Time Warp
Every GPS satellite carries atomic clocks, but time does not pass for them at exactly the same rate as it does on Earth. Each day, the atomic clocks gain roughly 38 microseconds compared with clocks on Earth. Engineers must correct this difference, or our GPS navigation systems would rapidly become unreliable. So when your phone finds your location, it is accounting for a tiny, real effect associated with time travel.
Mini Facts
1
Different observers experience different amounts of time.
2
Motion slows the satellites' clocks because of special relativity.
3
Weaker gravity speeds them up because of general relativity.
4
GPS (Global Positioning System) is a practical, everyday demonstration of Einstein's theories.