Gravity probe exceeds performance goals

http://www.bbc.com/news/science-environment-38897697

Gravity probe exceeds performance goals

By Jonathan Amos
BBC Science Correspondent, Boston

18 February 2017

From the section Science & Environment

The long-planned LISA space mission to detect gravitational waves looks as though it will be green lit shortly. Scientists working on a demonstration of its key measurement technologies say they have just beaten the sensitivity performance that will be required. The European Space Agency (Esa), which will operate the billion-euro mission, is now expected to "select" the project, perhaps as early as June.

The LISA venture intends to emulate the success of ground-based detectors. These have already witnessed the warping of space-time that occurs when black holes 10-20 times the mass of the Sun collide about a billion light-years from Earth.

LISA, however, aims to detect the coming together of truly gargantuan black holes, millions of times the mass of the Sun, all the way out to the edge of the observable Universe. Researchers will use this information to trace the evolution of the cosmos, from its earliest structures to the complex web of galaxies we see around us today.

The performance success of the measurement demonstration was announced here in Boston at the annual meeting of the American Association for the Advancement of Science (AAAS). It occurred on Esa's LISA "Pathfinder" (LPF) spacecraft that has been flying for just over a year. This probe is trialling parts of the laser interferometer that will eventually be used to detect passing gravitational waves.

When Pathfinder's instrumentation was set running it was hoped it would get within a factor of 10 of the sensitivity that would ultimately be needed by the LISA mission, proper. In the event, LPF not only matched this mark, but went on to exceed it after 12 months of experimentation.
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