The history of our galaxy is much more turbulent than previously thought. In the new work, published in Nature this week, astronomers said that hundreds of millions of years ago the milky Way almost collided with another galaxy and it shocked the movement of millions of stars within its disk.
From the Ground it seems to us that the milky Way appears as a bright band of stars in the night sky. But his real form is a complex spiral with curved sleeves that move around a convex center of the circle. The majority of stars in the milky Way are on disk and not in the center.
The clash with the galaxy: is it scary?
Exploring the map of the milky Way with the help of space Observatory “Gaia”, the researchers tried to determine the position and acceleration of six million stars. And suddenly found a helical structure resembling a snail, in the movements of these stars. If other stars in the galaxy are relatively stable ways of movement, they moved abruptly, like dust, suddenly fell from the air into the lungs. “At first we thought that there was an issue, so I spent time finding,” says lead author Teresa Antoya, an astrophysicist at the University of Barcelona in Spain.
The results of the study suggest that this pattern appeared between 300 million and 900 million years ago when the milky Way almost collided with orbiting dwarf galaxy Sagittarius.
“Looking at the speed of stars measured today, we can go past our galaxy and to observe the indignation of our galaxy,” says Antoya.
In the dwarf galaxy Sagittarius tens of millions of stars (and the milky Way from 100 billion to 400 billion), and is currently devouring our galaxy. Close passage near the Milky Way “knocked out” of the stars from their gravitational positions.
“We used to think our galaxy was relatively calm history. However, these results suggest that her past was a history of relations with other galaxies”.
I wonder what other consequences might be from that collision? Scientists have yet to explore this question. Share your opinion in our chat in Telegram.