Submarine measurement of the Newtonian gravitational constant

Abstract

We have measured the Newtonian gravitational constant using the ocean as an attracting mass and a research submersible as a platform for gravity measurements. Gravitational acceleration was measured along four continuous profiles to depths of 5000 m with a resolution of 0.1 mGal. These data, combined with satellite altimetry, sea surface and seafloor gravity measurements, and seafloor bathymetry, yield an estimate of G=(6.677\ifmmode\pm\else\textpm\fi{}0.013)\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}11}$ ${\mathrm{m}}^{3}$ ${\mathrm{s}}^{\mathrm{\ensuremath{-}}2}$ ${\mathrm{kg}}^{\mathrm{\ensuremath{-}}1}$; the fractional uncertainty is 2 parts in 1000. Within this accuracy, the submarine value for G is consistent with laboratory determinations.