Experimental Test of the Variability of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>G</mml:mi></mml:math>Using Viking Lander Ranging Data

Abstract

Results are presented from the analysis of solar system astrometric data, notably the range data to the Viking landers on Mars. A least-squares fit of the parameters of the solar system model to these data limits a simple time variation in the effective Newtonian gravitational constant to (0.2 \ifmmode\pm\else\textpm\fi{} 0.4) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}11}$ ${\mathrm{yr}}^{\ensuremath{-}1}$ and a rate of drift of atomic clocks relative to the implicit clock of relativistic dynamics to (0.1 \ifmmode\pm\else\textpm\fi{} 0.8) \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}11}$ ${\mathrm{yr}}^{\ensuremath{-}1}$. The error limits quoted are the result of uncertainties in the masses of the asteroids.