ESA's billion-star surveyor Gaia enters operational orbit

ESA's billion-star surveyor Gaia is now finally in its operational orbit around a gravitationally stable virtual point in space called 'L2', which is 1.5 million km from Earth.

Gaia has been travelling towards L2 since December 19, when, just before dawn local time, it was spectacularly launched from ESA's Spaceport in Kourou, French Guiana.

A day later, Gaia performed an important thruster burn to set course to its destination.

Recently, a critical manoeuvre boosted Gaia into its 263,000 x 707,000 x 370,000 km, 180 day-long orbit around L2. A small course correction will be made next week to complete the manoeuvre.

"Entering orbit around L2 is a rather complex endeavour, 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," David Milligan, Gaia spacecraft operations manager, said.

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.