The Gaia Satellite has unveiled the most accurate map of the Milky Way that has ever been drawn

The telescope, located 1.5 million kilometers away from the Earth opposite the Sun, has scanned 1% of our galaxy and has been able to provide information on 1.8 billion stars.

It is an unprecedented collection that offers scientists a true mine of information. The Gaia Space Telescope on Monday delivered its new data on nearly two billion stars in the Milky Way, with unprecedented precision that enables us to draw a multidimensional map of our galaxy, bubbling with life, with unparalleled precision.

“This is a wonderful day for astronomy, which opens the floodgates for new discoveries about the universe and our galaxies,” said Joseph Ashbacher, director general of the European Space Agency (ESA). The flagship scientific mission was launched in 2013.

1% of galaxies have been scanned but 1.8 billion stars have already been analyzed

“Before Gaïa, we had a medieval perspective, there were continents missing, poorly known country profiles. Since 2016, we have had a very precise vision of the continents as we found them on Earth. Released with new information “, explains Alejandra Resio-Blanco from C ডিte d’Azur Observatory.

The Space Observatory, located 1.5 million kilometers away from the Earth opposite the Sun, is part of its third data collection, aimed at mapping our galaxy at all its dimensions and thus understanding its source, its structure and its dynamics.

This image, published by the European Space Agency (ESA) on June 13, 2022, shows an artistic impression of the Milky Way and, above, an overlay (yellow-green) showing a sample position and density of young stars from Gaia Data Version 3.  Signs
This image, published by the European Space Agency (ESA) on June 13, 2022, shows an artistic impression of the Milky Way and, above, an overlay (yellow-green) showing a sample position and density of young stars from Gaia Data Version 3. The “you are here” sign points to the sun. European Space Agency / AFP

Equipped with two telescopes and a billion pixel photographic sensor, Gaia scans a very small fraction (only 1%) of the stars in our galaxy, measuring 100,000 light-years in diameter. However, it has analyzed 700 million data per day for 34 months and has been able to provide data of more than 1.8 billion stars.

Unprecedented accuracy

A host of unprecedented details, such as these 220 million photometric spectra, have been provided, which will make it possible to estimate the mass, color, temperature and age of stars for the first time.

And 2.5 million new chemical combinations, this “DNA” informs about the birthplace of stars and their journey through galaxies. Or 35 million radial velocities, which measure the displacement of stars and offer a new understanding of the motion of the Milky Way.

Not “turbulent” and “patachon”

Wonders for Scientists: For the first time, Gaia observed a “vibration” of a star, a tiny movement on the surface of a star that changes its shape. The discovery opens up “a gold mine for the asterosismology of the giant stars,” as Connie Arts of the University of Louvain (Belgium) explains, in their internal work, a member of the Gaia collaboration.

“At all levels, Gaia has exceeded expectations,” welcomed Franোয়াois Mignard, scientific manager of the Gaia mission in France.

These results thus paint a galaxy portrait “much more turbulent” than expected. “We thought it had reached a steady state, slowly turning itself on, like a liquid that gently shakes with a wooden spoon. But not at all!”, Develops Francois Mignard.

Accidents, in contrast to his “Patacon’s life”, are made up of unexpected movements, and this spiral is not as simple as he described. Does.

The final version is planned for 2030

It is home to a very diverse population of stars, some of which have not been there since the beginning but may have been “swallowed” along the way by interacting with nearby Sagittarius dwarf galaxies.

“Our galaxy is a great melting pot of stars,” Alexandra Resio-Blanco summed up. The level of accuracy of Gaia is such that it would “allow us to explore the galaxy’s past for more than 10 billion years,” added Anthony Brown, president of the international consortium DPAC, the ground processing chain of data streams transmitted by Gaia. .

The stars have the peculiarity of living for billions of years: their analysis is equivalent to the study of a fossil, informing us of the state of the galaxy at the time of its formation, underlining astronomers. With the help of the second catalog given in 2018, astronomers were able to show that our galaxy was “united” ten billion years ago.

The new catalog also offers unparalleled precise measurements for 156,000 asteroids in our solar system, breaking down a combination of 60,000. It will take five years to provide this third catalog of observations spread from 2014 to 2017. And it will have to wait until 2030 to get the final version, when Gaia will finish space scanning in 2025.

Leave a Comment