Gaia mission's second data batch offers "richest star map" of galaxy ever created

High-precision measurements of nearly 1.7 billion stars made by Gaia space observatory

The European Space Agency (ESA) has released the latest batch of findings from the Gaia mission, with scientists describing it as "the richest star map ever created of our galaxy".

Gaia is the name of the space observatory whose mission is to survey more than one billion stars in our galaxy and its local neighbourhood.

Its goal is to build the most precise 3D map of the Milky Way and answer questions about its structure, origin and evolution, notwithstanding the fact that it will only be surveying the brightest celestial objects in the galaxy, amounting to about one per cent of the total.

The studies were unveiled at a media briefing at the ILA Berlin Air and Space Show in Germany on Wednesday.

Describing the data contained in the release, astronomers said the mission has produced the richest star catalogue to date, including high-precision measurements of nearly 1.7 billion stars and revealing previously unseen details of our home Galaxy.

Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data.

Based on 22 months of charting the sky, the release demonstrates a host of new data, including positions, distance indicators and motions of more than one billion stars. There's also high-precision measurements of asteroids within our Solar System and stars beyond our own Milky Way.

This preliminary analysis could reveal fine details about the make-up of the Milky Way's stellar population, the scientists claimed, including how stars move, which is essential information for investigating the formation and evolution of our home galaxy.

"The observations collected by Gaia are redefining the foundations of astronomy," said Günther Hasinger, ESA director of science.

"Gaia is an ambitious mission that relies on a huge human collaboration to make sense of a large volume of highly complex data. It demonstrates the need for long-term projects to guarantee progress in space science and technology and to implement even more daring scientific missions of the coming decades."

Gaia was launched in December 2013 and started science operations the following year. The first data release, based on just over one year of observations, was published in 2016 and contains distances and motions of two million stars.