Measurement of the Newtonian Constant of Gravitation in Low Earth Orbit

The Newtonian Constant of Gravitation (G) quantifies the strength of gravity, a force which is both strong enough to dominate at astrophysical length scales and so weak as to be the most poorly measured and least understood force at human length scales.  Henry Cavendish first measured the strength of gravity in 1798 using a torsion balance, and most measurements of G until now have used closely-related methods.  However, it has now become clear that many measurements of G disagree with each other, and the scale of the disagreement exceeds the reported uncertainties of the measurements.  This implies that we either do not understand the errors in the measurements, or we do not understand gravity itself. Ambitious proposals of deep-space experiments to measure G to  unprecedented  precision  are  scientifically  attractive  but  technologically  daunting.   We are developing a new concept for a low earth orbit mission to measure G with simplified requirements based on the time-of-swing method in a magnetic trap. We propose to study outstanding scientific challenges in the design of this mission to determine the feasibility of a future program.

Contact Info