Progress in Lunar Laser Ranging Tests of Relativistic Gravity

Analyses of laser ranges to the Moon provide increasingly stringent limits on any violation of the equivalence principle (EP); they also enable several very accurate tests of relativistic gravity. These analyses give an EP test of $\ensuremath{\Delta}({M}_{G}/{M}_{I}{)}_{\mathrm{E}\mathrm{P}}=(\ensuremath{-}1.0\ifmmode\pm\else\textpm\fi{}1.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$. This result yields a strong equivalence principle (SEP) test of $\ensuremath{\Delta}({M}_{G}/{M}_{I}{)}_{\mathrm{S}\mathrm{E}\mathrm{P}}=(\ensuremath{-}2.0\ifmmode\pm\else\textpm\fi{}2.0)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}$. Also, the corresponding SEP violation parameter $\ensuremath{\eta}$…