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Science, Technology and Mission Design for the Laser Astrometric Test Of Relativity

Slava G. Turyshev·Michael Shao·Kenneth L. Nordtvedt Jr
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Abstract

The Laser Astrometric Test Of Relativity (LATOR) is a Michelson-Morley-type experiment designed to achieve a major improvement in the accuracy of the tests of relativistic gravity in the solar system. By using a combination of independent time-series of gravitational deflection of light in the immediate proximity to the Sun, along with measurements of the relativistic time delay on interplanetary scales (to a precision respectively better than 0.1 picoradians and 1 cm), LATOR will measure the key post-Newtonian Eddington parameter γwith accuracy of one part in a billion - a factor of 30,000 improvement compared to the present best result, Cassini's 2003 test. LATOR's primary measurement pushes to unprecedented accuracy the search for cosmologically relevant scalar-tensor modifications of gravity by looking for a remnant scalar field in today's solar system. We present a comprehensive discussion of the science objectives, proposed technology, mission and optical designs, as well as the expected performance of this fundamental physics experiment in space.

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Slava G. Turyshev, Michael Shao, Kenneth L. Nordtvedt Jr. 2006-02-09. Science, Technology and Mission Design for the Laser Astrometric Test Of Relativity. https://arxiv.org/abs/gr-qc/0601035

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