Gaia probe pins down precise positions of over a billion stars

On its way to assembling the most detailed 3D map ever made of our Milky Way galaxy, European Space Agency's Gaia probe has pinned down the precise position in the sky and the brightness of 1,142 million stars, astronomers working on the mission have said.

The first catalogue of more than a billion stars from Gaia satellite was published on Wednesday -- the largest all-sky survey of celestial objects to date.

The release also features the distances and the motions across the sky for more than two million stars.

"Gaia is at the forefront of astrometry, charting the sky at precisions that have never been achieved before," said Alvaro Gimenez, ESA's Director of Science.

"Today's release gives us a first impression of the extraordinary data that await us and that will revolutionise our understanding of how stars are distributed and move across our Galaxy," Gimenez said in a statement on Wednesday.

Launched in 2013 on a Soyuz-STB/Fregat-MT launch vehicle from the European Spaceport in Kourou, French Guiana, Gaia started its scientific work in July 2014.

This latest release is based on data collected during its first 14 months of scanning the sky, up to September 2015.

"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," Timo Prusti, Gaia project scientist at ESA, said.

Gaia probe was launched with the aim of making the largest, most precise three-dimensional map of our galaxy by surveying more than a thousand million stars.

At its heart, Gaia contains two optical telescopes that work with three science instruments to precisely determine the location of stars and their velocities, and to split their light into a spectrum for analysis.

During its planned five-year mission, the spacecraft spins slowly, sweeping the two telescopes across the entire celestial sphere.

As the detectors repeatedly measure the position of each celestial object, they will detect any changes in the object's motion through space.

--IANS

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