Physics @ Berkeley
Physics in the News
Title: Ground-based Lasers Map Earth's Magnetic Field
Date: 02/14/2011
Publication: UC Berkeley News Center
Editor: Robert Sanders
Extended Text:

Mapping the Earth’s magnetic field – to find oil, track storms or probe the planet’s interior – typically requires expensive satellites.

University of California, Berkeley, physicists have now come up with a much cheaper way to measure the Earth’s magnetic field using only a ground-based laser.

The method involves exciting sodium atoms in a layer 90 kilometers (60 miles) above the surface and measuring the light they give off.