LISA Pathfinder was a test mission of the European Space Agency ESA for the LISA mission. LISA Pathfinder demonstrated central LISA technologies with which the first gravitational wave observatory in space will observe low-frequency gravitational waves.
Perfect free fall
LISA Pathfinder places two test-masses in a nearly perfect gravitational free-fall and controls and measures their motion with unprecedented accuracy. This is achieved through state-of-the-art technology comprising inertial sensors, a laser metrology system, a drag-free control system and an ultra-precise micro-propulsion system. All these technologies are essential not only for LISA - they also lie at the heart of any future space-based test of Einstein's General Relativity. The Albert Einstein Institute is one of the leading mission partners.
LISA Pathfinder was launched on December 3, 2015, at 5:04 CET onboard a Vega rocket from the European spaceport in Kourou, French Guiana.
LISA Pathfinder results
In early June 2016, the LISA Pathfinder Science Team published results from the first two months of operations. They showed that LISA Pathfinder has successfully demonstrated the technology for a gravitational wave observatory in space such as LISA.
The final results from LISA Pathfinder, published in February 2018 exceed the requirements for future gravitational-wave observatory LISA by far. This demonstration of near-perfect free fall of two test masses over a wide frequency band is a critical benchmark for the LISA mission and future multi-messenger astronomy in collaboration with other (electromagnetic-wave) observatories.