Gaia Liftoff. Photo: ESA

[Via Satellite 01-08-2014] The European Space Agency’s (ESA) billion-star surveyor Gaia is now in its operational orbit at Lagrange point 2 (L2), a gravitationally stable virtual point located 1.5 million kilometers from Earth.

Gaia has been travelling toward L2 since Dec. 19, 2013 when it was launched from Europe’s Spaceport in Kourou, French Guiana. A day later, Gaia performed an important thruster burn to set course to its destination. Last night, another manoeuver boosted Gaia into its 180 day-long orbit around L2. A small course correction will be made next week to complete the manoeuver.

“Entering orbit around L2 is a rather complex endeavor, achieved by firing Gaia’s thrusters in such a way as to push the spacecraft in the desired direction whilst keeping the Sun away from the delicate science instruments,” said David Milligan, Gaia spacecraft operations manager, ESA.

Once the spacecraft instruments have been fully tested and calibrated — an activity that started en route to L2 and will continue for another four months — Gaia will be ready to enter a five-year operational phase. The Gaia telescope is tasked with making very accurate observations of approximately one billion stars, charting their precise positions and motions, as well as their temperatures, luminosities and compositions. This enormous census will result in the most accurate 3D map yet of the Milky Way and allow astronomers to determine the origin and the evolution of our galaxy.