Astronomers are dizzy: the Gaia space telescope delivered its new data on nearly two billion stars in the Milky Way on Monday, with incredible accuracy making it possible to draw a map of our galaxy, which is bursting with life. .
This is an amazing day for astronomy, opening doors for new discoveries about the Universe and our galaxy.said Josef Aschbacher, Director General of the European Space Agency (ESA) during the presentation of the results of Gaia, one of the agency’s chief scientific missions launched in 2013.
The galaxy observatory, located 1.5 million kilometers from Earth, opposite the Sun, is in its third data harvest, which aims to map our galaxy in all its dimensions, and thus understand its origin, its structure and dynamics.
Equipped with two telescopes and a billion pixel photographic sensor, Gaia scans a very small fraction (almost 1%) of the stars in our galaxy, whose diameter is 100,000 light-years.
The numbers announced Monday are unbelievable: by analyzing 700 million data sent to earth every day over 34 months, Gaia has been able to provide information on more than 1.8 billion stars.
A host of unprecedented details are delivered, such as these 220 million photometric spectra, that will make it possible to estimate for the first time the mass, color, temperature and age of stars. And 2.5 million new chemical compositions, it DNA providing information on the birthplace of stars, and their travel in space.
Or 35 million radial velocities, which measures the displacement of stars and offers new understanding of the movements of the Milky Way.
Surprise for scientists: Gaia saw for the first time chills stellar, small movements on the surface of a star that change its shape. The discovery opens up a gold mine for the asteroseismology of massive starsespecially their internal work, explained Conny Aerts, of the University of Leuven, Belgium, member of the Gaia collaboration.
On all levels, Gaia exceeded expectationsFrançois Mignard, scientific manager of the Gaia mission for France, was hired at Agence France-Presse (AFP).
The results, which resulted in approximately fifty scientific articles in the process, painted a picture of a galaxy more messy than expected, the astronomer of the Observatory of the Côte d’Azur told AFP.
It is thought to reach a stationary state, slowly rotating, like a liquid gently stirred with a wooden spoon. But not at all! explained François Mignard.
His event -filled life is the opposite consisting of accidents, of unexpected movements and not as simple as this spiral he describes. For example, our solar system “does not simply rotate in a perpendicular plane; it is up and it is down, above and belowsaid François Mignard.
It is also home to a very diverse population of stars, some of which have not been there since time immemorial, but may swallowed along with interactions with the nearby Sagittarius Dwarf Galaxy.
Our galaxy is a beautiful crucible of starssummarizes Alejandra Recio-Blanco, from the Observatory of the Côte d’Azur.
Gaia’s level of accuracy is like that will allow us to trace the past of the Milky Way over 10 billion yearsAnthony Brown, president of the international consortium DPAC, added the ground processing chain for the data flow sent by Gaia.
Stars have a particular life span of billions of years: examining them is tantamount to studying a fossil, informing us about the state of the galaxy during its formation, astronomers underline.
In the second catalog, delivered in 2018, astronomers have shown that our galaxy exists integrated along with another 10 billion years ago.
The new catalog also offers measurements of unparalleled accuracy for 156,000 asteroids in our solar system by dissecting the composition of 60,000 of them.
It will take five years to deliver the third catalog of these observations that stretch from 2014 to 2017. And we will have to wait until 2030 to get the final version, when Gaia has finished scanning space, in 2025.
France Media Agency
Source: Radio-Canada
