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The global positioning system, relativity, and extraterrestrial navigation



Neil Ashby


Relativistic effects play an important role in the performance of the Global Positioning System (GPS) and in world-wide time comparisons. The GPS has provided a model for algorithms that take relativistic effects into account. In the future exploration of space, analogous considerations will be necessary for the dissemination of time and for navigation. We discuss relativistic effects that are important for the navigation system such as at Mars. We describe relativistic principles and effects that are essential for navigation systems, and apply them to navigation satellites carrying atomic clocks in orbit about Mars, and time transfer between Mars and Earth. It is shown that, as in the GPS, relativistic effects are not negligible.
Proceedings Title
Proceedings IAU Symposium, No. 261
Conference Dates
April 27-May 1, 2009
Conference Location
Virginia Beach, VA
Conference Title
Relativity in Fundamental Astronomy - Dynamics, Reference Frames and Data Analysis


relativity, navigation, reference systems, time, GPS


Ashby, N. (2009), The global positioning system, relativity, and extraterrestrial navigation, Proceedings IAU Symposium, No. 261, Virginia Beach, VA, [online], (Accessed July 12, 2024)


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Created April 27, 2009, Updated February 19, 2017