Gaia, the European Space Agency (ESA) satellite that maps the Milky Way, has completed the sky-scanning phase of its mission, in which it has accumulated more than three trillion observations of some two billion stars and other objects over the past decade, revolutionizing the view of our galaxy and our cosmic neighbourhood.
Since its beginning, the Gaia mission, ESA's most ambitious project to study the history and structure of the Milky Way, has involved a team of astronomers and engineers from the Department of Quantum Physics and Astrophysics, the Institute of Cosmos Sciences (ICCUB) of the University of Barcelona and the Institute of Space Studies of Catalonia (IEEC).
Gaia's fuel, launched on 19 December 2013, is about to run out: it uses about ten grams of gas per day to keep spinning with millimetre precision. But this is far from the end of the mission: technology tests are scheduled for the coming weeks before Gaia moves to its 'retirement' orbit, and two data releases are planned for 2026 and later this decade, the so-called DR4 and the final catalogue, DR5.
Carole Mundell, ESA Director of Science, says: "Today marks the end of science observations and we are celebrating this incredible mission that has exceeded all our expectations, lasting for almost twice its originally foreseen lifetime".
"The data collected by Gaia has given us with unique insights into the origin and evolution of our Milky Way, and has also transformed astrophysics and Solar System science in ways we have yet to fully appreciate", continues Mundell. "Gaia has built on unique European excellence in astrometry and will leave a long-lasting legacy for future generations", she adds.
Moreover, Johannes Sahlmann, Gaia project scientist, says that "after eleven years in space and surviving micrometeorite impacts and solar storms along the way, Gaia has finished collecting scientific data. Now all eyes turn towards the preparation of the next data releases". "I am thrilled with the performance of this incredible mission, and excited about the discoveries that await us", he says.
