If you live in the southern hemisphere of the Earth, you'll probably be able to see some of the stars in a newly-established space river that has been flowing through the Milky Way for hundreds of millions of years.
Astronomers say that the freshly discovered giant star cluster passes relatively close to our solar system. The cluster contains at least 4000 stars that are constantly moving together across the night sky like a river covering almost the entire southern sky. To be clear, the stars are not new discoveries: the fact that they are in a group together is the revelation here.
"Most star clusters in the galactic disk are scattered quickly after birth because they do not contain enough stars to create. deep gravitational potential, or, in other words, they do not have enough glue to keep them together, "says Stefan Meigast, lead author of the study, published today in Astronomy and Astrophysics, an astronomer working at the University of Vienna, Austria.
Even in the immediate sunny neighborhood there are several clusters with enough stellar mass that remain bound for several hundred million years. So, in principle, such disk scraps of clusters or associations should also be part of the Milky Way Disk.
It is believed that the star river was formed about a billion years ago and has surrounded the Milky Way.
The stellar stream projection is centered around the southern Galactic Pole. The Milky Way is curved around an arc and the red dots are the stars in the cluster. Image credit: Astronomy & Astrophsyics
Researchers at the University of Vienna and Harvard University noticed the stellar stream by carefully mapping the 200-star 3D motion using data from the European Gaia spacecraft. The spread and movements of the stars show signs that all of them have been enclosed in a beech, and are tearing apart from the gravitational field of the Milky Way.
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"Identifying the nearby streams of discs is like searching for the proverbial needle in a haystack," said João Alves, co-author of the article and professor of astrophysics at the Viennese university.
"Astronomers have long been watching and going through this new stream because it covers most of the night sky, but only now realizes it is there, and it is enormous and shockingly close. towards the sun. Finding things close to home is very useful, that is, they are not too weak or too blurry for further detailed exploration, as astronomers dream. "
The team hopes that studying the river by winding stars will give them a better understanding of the massive and gravitational field of the Milky Way, and helped scientists clarify how the stars appeared