The nearest to the Milky Way - Andromeda Galaxy - was born as a result of the collision of two smaller galaxies, astronomers have discovered. The international team conducted computer simulations of the time evolution of the Andromeda galaxy.
The results suggest that the two galaxies have faced some nine billion years ago, and finally dissolved in each other about 5.5 billion years ago.
The study was published in the journal Astrophysical Journal. Lead author, Francis Hammer of the Paris Observatory, France, said that although the scientists were able to discover galaxies at the edge of the universe, but we are still gaps in knowledge about our immediate neighbors, known as the Local Group of galaxies.
In the Local Group consists of more than 50 galaxies, most of them - it’s the Milky Way and the Andromeda Galaxy.
"Many astronomers, especially specialists in this field, thought that the Andromeda galaxy could be the result of a large merger," - said Dr. Hammer.
"But only now able to test and even set the date of the event." The researcher explained that the opening of his team, "may force completely revise all our knowledge about the Local Group - and it can also be forced to change our ideas about the amount of dark matter in galaxies."
Using computer simulations, the astronomers were able to reproduce most of the specific features of the Andromeda galaxy: a large thin disk including its giant ring of gas and dust, the massive central projection, a giant thick galactic "disc" and a giant stream of old stars.
Simulations were performed on high-performance computers of the National Astronomical Observatories of China and the Paris Observatory.
The scientists used more than eight million particles to simulate stars, gas and dark matter. Dr. Hammer said that the study may shed light on the formation of our galaxy.
"This does not mean that the Milky Way could be formed in a similar way - [maybe how it was], but [it ought to have happened] much earlier," - he said. We will tell you the exciting news from the horse’s mouth.