Why do GPS satellites need time dilation corrections?

[binbots]

I always hear about the GPS system having to slow down there clocks to keep accurate time with clocks on earth. Is the simple reason for this is that the clock on the satellite has to travel further and faster than the clock on Earth to make a complete rotation around the earth? Is this was relativity means?

 

[bcrowell]

No, it means that time actually flows at different rates depending on gravity and on motion.

This may be helpful: http://en.wikipedia.org/wiki/Hafele-Keating_experiment

 

[binbots]

Thanks. That sums it up nice.

 

[russ_watters]

Crackpottery and responses deleted, thread reopend.

This forum exists for discussing real science. Legitimate questions from people trying to learn Relativity are acceptable here. Anti-Relativity crackpottery is not.

Carry on.