[ad_1]
The researchers found traces of a collision between the Milky Way and another galaxy.
Our galaxy is old. The best estimates indicate that the Milky Way is only a few hundred million years younger than the universe, about 13 billion years old.
The galaxy has had time to participate in some of them, including collisions on a cosmic scale. A research group is now seeing traces of a collision with another dwarf galaxy that would have occurred a long time ago. Together 10 billion years.
And scientists know that we are on a collision course with another galaxy, even though it is also very long.
Surrounded by stars
This is a special structure in the galaxy called "halo", which is a spherical structure that surrounds the inner part of our galaxy.
The researchers used information from the Gaia telescope, which compiles a map of the galaxy. The telescope is also used to reveal the chemical structure of different areas of stars.
Based on this information, as well as a repertoire of stars called APOGEE, the researchers believe they have found traces of a massive collision. You can see a simulation of the collision in the video below.
The stars of this second galaxy (red stars), which scientists have named Gaia-Enceladus, have gathered in the inner ring and in this spherical structure that you can watch on video.
Based on the simulations, the researchers believe that this dwarf galaxy was about a quarter of the size of the Milky Way, which means that it was slightly larger than the Great Sky of Magellan, our nearest galactic neighbor. It is located about 170 000 light-years away.
Read also: 14 galaxies on the collision course
Andromeda
But researchers can also see a collision in our galactic future. The Milky Way will collide with the Andromeda galaxy in about four billion years.
The Andromeda galaxy, located about 2.5 million light years away from us. (Photo: Adam Evans / CC BY 2.0)
Then, the two galaxies will become a gig galaxy. We do not know how such a collision will actually be experienced. It is so far between each star that collisions between one and a star disappear unlikely.
Due to gravitational disturbances related to the collision, it is conceivable that the solar system can be ejected from the galaxy, but its probability is also low.
reference:
Helmi et al .: The fusion which led to the formation of the internal stellar halo and the thick disc of the Milky Way. Nature, 2018. DOI: 10.1038 / s41586-018-0625-x. resume
The case was first published by Research.no
[ad_2]
Source link
