In: Physics
Consider a satellite orbiting the earth. Using the spacetime metric for a weak Newtonian gravitational field, what is the difference in the time to complete one orbit as measured by the satellite and as measured by distant observers at rest.
Assumption: The satellite will orbit earth at 1200 km.
r = 1200 + RE = 1200 + 6378 (Earth's equatorial radius) = 7578 km
V = Sqrt (Gme/r) = sqrt{(6.673*10^-11*5.974*10^24)/(7578*10^3)}=7252m/s = 7.25km/sec
T =2*pi*r/V=6562 seconds =109 minutes measured at Satellite.
As per Special Relativity, assume time runs 5000 nanoseconds per
day slower for a satellite relative to us on Earth.
As per Weaker General Newtonian Gravitation Relativity it is
possible to calculate that time goes faster for a satellite by 6
times minimum the Special relativity measured nanoseconds (30000
per day, due to the satellite being 1200km above the Earth
(therefore in weaker gravity).
Time difference is 25,000 (30,000 – 5,000) nanoseconds faster per day for a measurement between satellite and stationary distant observers at rest on Earth.