February 23, 2017

Lisa Pathfinder

On 3 December 2015, the LISA Pathfinder satellite was launched from Kourou en route to the first Sun-Earth Lagrangian point. Its mission: to test technologies able to directly detect the gravitational waves predicted by Albert Einstein.

The European Space Agency (ESA) is pursuing an ambitious physics mission about the gravitational Universe (L3 mission) that aims to directly observe gravitational waves—the tiny ripples in the fabric of space-time predicted by Einstein’s theory of general relativity—using 3 satellites forming a giant optical interferometer. The presence of these waves will be signalled by minute relative movements between 2 test masses in free fall at the end of each of the interferometer’s arms.

LISA Pathfinder is a scaled-down model of an interferometer arm packed into a single satellite that tests key technologies required to place the 2 test masses in perfect free-fall conditions and measure their relative movement with unprecedented precision. LISA Pathfinder also draws on the very latest developments to minimize other forces acting on the masses housed inside the LTP instrument (LISA Technology Package) and to measure their movement. With its inertial sensors, laser metrology, drag-free control and ultra-precise micro-propulsion systems, it is a truly ground-breaking mission.

CNES and its partners in the French consortium coordinated by the APC astro-particles and cosmology laboratory are involved in this ESA-led mission for which they are supplying a subsystem of the LTP instrument’s optical bench. They will also be performing operational science data analysis once the satellite is in orbit.