The European Space Agency released the largest ever full-sky survey of celestial objects last week — a map of two million stars and data on their distances and motions through the sky. The release is the first batch of more than one billion that the agency hopes to catalog using its Gaia satellite in the coming year.
“Gaia is at the forefront of astrometry, charting the sky at precisions that have never been achieved before,” Alvaro Giménez, ESA’s Director of Science, said in a press release. “Today’s release gives us a first impression of the extraordinary data that await us and that will revolutionize our understanding of how stars are distributed and move across our Galaxy.”
Gaia was launched in December 2013 and the data was collected by the satellite during its first 14 months in operation, once scientists solved a series of technical issues following its launch.
The map includes images of galaxies, open clusters, and globular clusters in our celestial neighborhood.
“The beautiful map we are publishing today shows the density of stars measured by Gaia across the entire sky, and confirms that it collected superb data during its first year of operations,” said Timo Prusti, Gaia project scientist at ESA.
Along with information about distance, location, and movements of the stars, the satellite also measured the stars’ light curves, which will help scientists analyze their internal structures.
Gaia is ESA’s second star-gazing satellite, the first of which mapped some 100,000 stars. The team behind Gaia intends to image an unprecedented one billion stars, which the agency hopes to release by the end of 2017.
To attain such clear images, Gaia’s telescope must be detailed and accurate, with a focus plane that can capture over a billion objects and a precision comparable to targeting a coin from across the Atlantic Ocean.