The LISA Pathfinder scientific space probe to be launched by Arianespace's next Vega flight has received its propellant load for a mission to study the ripples in space-time predicted by Albert Einstein's General Theory of Relativity.

LISA Pathfinder was "topped off" in the Spaceport's S5 payload preparation facility, taking it one step closer to a December 2 launch from French Guiana on Arianespace Flight VV06 - the light-lift Vega's sixth launch since entering service in 2012.

The European Space Agency space probe was built under the responsibility of prime contractor Airbus Defence and Space, and will be placed by Vega in an initial elliptical Earth orbit. The spacecraft's own propulsion module will be utilized to reach the operational orbit around the first Sun-Earth Lagrange point (L1) - located approximately 1.5 million kilometers from Earth.

To evaluate the concept of low-frequency gravitational wave detection, LISA Pathfinder will put two test masses in a near-perfect gravitational free fall, controlling and measuring their motion with unprecedented accuracy.

The test masses will be suspended inside their own vacuum containers, with LISA Pathfinder designed as the quietest spacecraft ever launched - allowing for extremely small distance measurements with the masses to be performed by an onboard interferometer.

Vega is the smallest member of Arianespace's launcher family, tailored to accommodate scientific, institutional, governmental and commercial satellites. It operates along with the medium-lift Soyuz and heavy-lift Ariane 5 at the Spaceport.

The development of Vega was carried out in a multinationally-financed European Space Agency program, with the launcher's design authority and prime contractor role performed by Italy's ELV company - a joint venture of Avio and the Italian Space Agency.