Washington, Jul 4.- Astronomers discovered an ancient and dramatic frontal collision between the so-called Sausage Galaxy and the Milky Way that reformed the structure of the Milky Way, forming both its internal protuberance and its external halo, specialized media reported today.
The members of the international team of experts say that the cosmic accident of about eight or 10 billion years ago shattered the small galaxy and its stars are now moving in very radial, long and narrow needle-like orbits.
These remains spread throughout all the inner parts of the Milky Way, creating the protuberance in the center of the galaxy and the surrounding stellar halo.
The paths of the stars take them very close to the center of our galaxy. This is a revealing sign that the dwarf galaxy entered a truly eccentric orbit and its fate was sealed,' scientist Vasily Belokurov assures.
On the other hand, Wyn Evans from Cambridge University explained that the star paths of the galactic fusion earned them the nickname 'Gaia sausage', the only thing left of the last great fusion of the Milky Way.
And although today the Milky Way continues to collide with other galaxies, such as the flimsy dwarf galaxy of Sagittarius, the 'Sausage' was more massive. Its total mass in gas, stars and dark matter was more than ten billion times the mass of our sun.
Scientists agree that after the impact the Milky Way disk was probably swollen or even fractured and would have needed to grow back.
While there have been many dwarf satellite galaxies falling into the Milky Way throughout his life, this was the largest of them all,' said Sergey Koposov of Carnegie Mellon University, a scholar of the kinematics of stars and globular clusters originating in the sausage galaxy.
This research also identified at least eight large spherical groups of stars called globular clusters which were brought into the Milky Way by the sausage galaxy.
Some experts coincide that small galaxies generally do not have globular clusters of their own, so the sausage galaxy must have been large enough to house a collection of clusters.