Free Fall to the Nth Degree

LIGO did the deed in finally proving gravitational waves exist. Now, LISA, when it becomes operational, will be able to sense gravitational waves from various sources throughout the known universe. Pretty cool without question.

Then, on March 1, the probe (LISA Pathfinder) began its six-month science mission, performing a variety of experiments, including a crucial one that attempted to place the test masses in a virtually perfect free fall. LISA Pathfinder used its thrusters to maneuver precisely, shielding the masses from external forces — and did so incredibly effectively.

Artist's impression showing the core of the LISA Pathfinder technology package, which consists of two gold-platinum cubes kept in close to a perfect free-fall state.

Credit: ESA/ATG medialab

The relative acceleration between the two test masses was lower than 1 part in 10 millionths of a billionth of Earth’s gravitational acceleration, mission team members said. This result — which is based on the first two months of data collection, and was published today in the journal Physical Review Letters — proves out the key technologies required to detect and study gravitational waves in space, Danzmann said.

"At the precision reached by LISA Pathfinder, a full-scale gravitational-wave observatory in space like LISA would be able to detect fluctuations caused by the mergers of supermassive black holes in galaxies anywhere in the universe," he said.

Ain't science grand? :)