Anjum Haseeb asks:
What is NAVSTAR navigation system?
It consists of at least 24 satellites in 6 orbital planes.
Each satellite circles the Earth twice every day at an altitude of 20,200 kilometers.
The satellites are equipped with atomic clocks . They continuously broadcast the precise time according to their own clock, along with information including the orbital elements of their own motion, as determined by a set of ground-based observatories.
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