Gravitation Physics Laboratory

WHERE: Located within the The Fitzner/Eberhardt Arid Lands Ecology Reserve, inside a former Nike missile launch site.  This laboratory has operated for over 15 years: the first visit in Spring of 1994, and it will be vacant in Fall 2011. It is ideally suited for the extremely sensitive detectors because of its remote, arid, microseismically quiet, and restricted location as well as proximity to Rattlesnake mountain.

Research groups from the University of Washington and the University of California at Irvine, supported by Battelle for the Pacific Northwest National Laboratory (PNNL), a National Laboratory of the U.S. Department of Energy.


Safety is top priority, and the PNNL facility use management personnel are the best. Access to the site is restricted in order to avoid disturbing the research, however one may arrange a visit by contacting Roy Gephart at PNNL at 509-376-1421.

WHAT: Presently, precision measurements of the nature of gravity are being performed for the National Science Foundation. The universal gravitational strength constant, the distance dependence, and the material dependence are being investigated. In the late 1500's Galileo was apocryphally said to have dropped a cannon ball and wooden ball of the tower of Pisa and found they hit the ground at the same time. Then, 200 years ago Cavendish developed the torsion pendulum to measure the Earth's density. Today, torsion pendulums at room temperature and cryogenic temperature are used here to measure horizontal gravitational forces extremely precisely. For example, a force one 10-billionth the weight of a postage stamp can be measured in an hour. Additional research information is available at UW and UCI.

Scroll around the panoramic view from the top of the facility entrance berm.

(floorplan is approx 20 feet underground)
click on the red arrows to see numbered photos
Gravitation research was limited to the South bunker; photos of North bunker provided for completeness.

Persons imaged in photos: E.C.Berg(UCI), R.M.Bonicalzi(UW), P.E.Boynton(UW), J.Bucay(UCI), W.D.Cross(UCI), K.McKenney(UW), M.W.Moore(UW), R.D.Newman(UCI). updated 1/19/2014