[ad_1]
A sausage-shaped galaxy shattered in our Milky Way billions of years ago, changing the shape of our galaxy forever.
An international team of astronomers discovered that an ancient intergalactic collision occurred between the Milky Way and a dwarf galaxy dubbed "Gaia Sausage" there are about 8 billion to 10 billion. ; years. Researchers believe this epic crash may have helped shape the central bulge and outer halo of the Milky Way stars, according to a statement.
"The collision shredded the dwarf," said Vasily Belokurov, a contributor to the discovery. who is the senior author on the sausage discovery papers and a researcher at the University of Cambridge in the UK and the Center for Computational Astrophysics at the Flatiron Institute in New York. However, after the collision, the stars left by the sausage galaxy shifted into radial orbits in long, narrow patterns, according to the statement. The galaxy of sausage takes its name from this radial sausage-shaped orbit. [When Galaxies Collide: Amazing Photos of Cosmic Crashes]
The sausage-shaped path in which these stars are in orbit is what has shaken the researchers about this collision, because this path is near the center of our galaxy. "It's a tell-tale sign that the dwarf galaxy has entered a truly eccentric orbit and its fate has been sealed," Belokurov said in a statement
Researchers believe this newly discovered collision could have lasting effects on our galaxy. Belokurov told Space.com that the impact "must have completely reshaped the Milky Way."
Belokurov and the other researchers are still exploring the consequences of this collision, and none of them has been confirmed. But researchers believe that the collision could have had three main effects.
First, the Milky Way disk was probably bloated or even potentially "completely destroyed", forcing it to fend off, according to Belokurov. Second, the debris from the collision could have created the "bulge" at the center of the Milky Way. Third, this collision and scattering of stars and debris may also have created a "stellar halo" around our galaxy.
Although the collision of the galaxy of sausages is not the only example of another galaxy on the Milky Way, the largest dwarf satellite galaxy known to have collided with ours, the researchers said . However, because the sausage galaxy is so big, it has caused more damage than usual, they added. In addition, the more radial a galaxy is, the more likely it is to cause damage in a collision, Belokurov said in an interview. [How the Gaia Galaxy-Mapping Satellite Works (Infographic)]
Now that researchers are aware of the collision, they plan to further study its effects and even "study the chemistry of the stars that accompany the sausage [galaxy]", according to Belokurov.
The discovery is detailed in articles published in the journal Monthly Notices of the Royal Astronomical Society, The Astrophysical Journal Letters and the pre-printed site arXiv.org
Email Chelsea Gohd at cgohd @ space.com or the following @chelsea_gohd . Follow us on Facebook and Google+ . Original article on Space.com.
Source link
