The Gaia Space Telescope has presented its new data on nearly two billion stars in the Milky Way on Monday, with incredible precision that makes it possible to map a galaxy teeming with life. “It is a wonderful day for astronomy, and opens the door to new discoveries regarding the universe and our galaxy,” said ESA Director General Joseph Asbacher, while presenting the results of the Gaia telescope, one of the agency’s most important missions launched in 2013.
This is the third data-collection mission of the space observatory, which is stationed 1.5 million kilometers from the Earth versus the Sun, and aims to map our galaxy in all its dimensions, and thus understand its origin, structure and dynamics.
Equipped with two telescopes and a photographic sensor with a resolution of a billion pixels, Gaia is scanning a tiny fraction (barely 1%) of the stars in our galaxy 100,000 light-years across, and even further afield.
The numbers revealed on Monday are staggering: By analyzing the 700 million data sent to Earth every day, over a period of 34 months, Gaia was able to provide information regarding more than 1.8 billion stars.
– “Goldmine”
The mission provides an unprecedented set of detail, including 220 million spectra of spectra, which will make it possible for the first time to estimate the mass, colour, temperature and age of stars. It also introduces 2.5 million new chemical structures, a “nucleic acid” that tells us where stars are born and their journey through the galaxy.
.Gaia also provides data on 35 million radial velocities that measure their movement and provide a new understanding of the motions in the Milky Way. The biggest surprise is that Gaia has observed for the first time stellar “tremors”, which are small movements on the surface of a star that changes its shape.
This discovery opens up a “gold mine for stellar science at the level of massive stars,” that is, their inner workings, explained Connie Aerts of the Belgian University of Louvain, a collaborating member of the Gaia mission.
The scientific director of the Gaia mission in France, Francois Minniard, says that this mission “exceeds expectations on all levels.”
The astronomer from the Observatory of the French coastal Côte d’Azur told “AFP” that the results that contributed to writing regarding fifty scientific articles, paint a picture of a galaxy “more turbulent” than expected.
