Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

A New Determination of G



J P. Schwarz, J E. Faller, T M. Niebauer, F Klopping, D S. Robertson, G Sasagawa


A short test run of the apparatus was conducted in February 1997 and gave promising results. A difference signal of about 80 υGal was observed, with reasonable scatter in G values from day to day. A sample of the data is seen in figure 1. This scatter currently limits the precision of the experiment. At the Table Mountain Gravity Observatory where the experiment is located, 6 υGal is a low-end estimate of the scatter of drops made by a standard FG-5. Assuming that this noise is Gaussian, a two week data run would give a differential precision of .04 υGal for a signal of about 80 υGal. This would be a .05 % experiment in G, if the other error sources are kept below this noise level. To increase the precision by an additional factor of two, it would be necessary to run the experiment for two months which is not practical. A two week data is feasible, and thus we expect to make a .05 % determination of G which will significantly contribute to the resolution of discrepancies in recent measurements.
A.G.U. Chapman Conference on Microg-1 Gravimetry


fundamental standards, gravity, Newtonian constant of gravitation, precision measurement


Schwarz, J. , Faller, J. , Niebauer, T. , Klopping, F. , Robertson, D. and Sasagawa, G. (2021), A New Determination of G, A.G.U. Chapman Conference on Microg-1 Gravimetry (Accessed April 21, 2024)
Created October 12, 2021