European “Disco Ball” Probe to Test Einstein’s Relativity

The LARES satellite undergoes preparations for launch 

at Europe's spaceport in French Guiana. 

Photograph courtesy Stephane Corvaja, ESA

Launched today aboard the European Space Agency’s new Vega rocket, a low-cost space probe will test Albert Einstein’s general theory of relativity—and could do so better than a recent NASA mission that cost nearly a hundred times more, managers say.

In the mid-2000s, after more than 40 years of development, the $800-million Stanford University-led Gravity Probe B detected frame dragging. This effect, predicted by Einstein’s theory, is caused by Earth’s rotation dragging the fabric of space and time along with it.
(Related: “‘Death Dance’ Stars Found—May Help Prove Einstein Right.”)

But because of a technical glitch, the NASA craft was able to measure frame dragging with an estimated accuracy of no better than 20 percent.

Scientists working with the new Italian probe, which cost $10 million (U.S.) to build, hope to improve on those readings.

“If we reach one percent [accuracy]—and I am fairly confident we will—we’ll have an order of magnitude’s improvement” over Gravity Probe B’s measurement, said mission leader Ignazio Ciufolini, of the University of Salento in Lecce, Italy.               More