Research Abstracts Online
January 2010 - March 2011
University of Minnesota Twin Cities
PI: Rolf R. Engel
Gravity Measurements at the Soudan Mine Underground Physics Laboratory
The University of Minnesota Underground Physics Laboratory, at an abandoned iron ore mine in Soudan, Minnesota, provides an environment that has a stable ambient temperature and is remote from storms and motorized traffic. These features are suited for the continuous monitoring of gravity. By comparing surface and subterranean gravity measurements, evidence for or against gravitational shielding will be collected. An estimated 647 meters of vertical earth separates the subterranean monitoring site from the surface. The prevailing view is that gravitational shielding does not exist. Exceptions to this concept would call for a modification of both Newton's laws of gravity and the tenants of general relativity. A sensitive, vertical gravity meter will measure relative gravity every second to +/-1 microGal. The projected data processing will entail generating graphs that display changes in gravity over time. If statistically significant evidence for instances of gravitational shielding is obtained then the circumstances associated with these events will be investigated.