In a newly published paper, astronomers argue that the collision of the Milky Way and the Andromeda galaxy, which has been scaring people for decades, will not happen. This conclusion was made based on an analysis of the transverse motion of neighboring galaxies.
Collision of galaxies
For several decades now, scientists have predicted that in the next 5 billion years, the Milky Way will collide with the nearest large galaxy in the Andromeda constellation. However, new research shows that this may not happen.
It has been known for almost a century that the Andromeda galaxy and the Milky Way are approaching for almost a century, since scientists first determined its position in space and motion vector. Further refinements led to the conclusion that they will merge in the future. At the same time, it has been emphasized from the very beginning that this will not have catastrophic consequences for the Earth.
However, the fact is that all the predictions so far have been made only based on measuring Andromeda’s speed along our line of sight. It’s relatively easy to estimate from the Doppler shift. However, there is also a longitudinal component, that is, how these star systems move in a plane perpendicular to this beam.
Transverse movement
Until now, it was believed that the magnitude of Andromeda’s transverse motion was insignificant, meaning that no matter how much it moved away from us, a collision would still be unavoidable. However, no one has ever determined this value exactly, because it is difficult.
In the new study, the researchers took huge amounts of data collected by the Hubble and Gaia telescopes and analyzed them. They also took into account the gravitational influence of the Triangle Galaxy and the Large Magellanic Cloud, which are also part of the system.
The result was the conclusion that the transverse component of Andromeda’s velocity is significantly higher than previously thought. The probability of collision and merger is only 50%. Many simulations have been conducted, and in most of them, the two-star systems do not merge at all over the next 10 billion years, but remain two close satellites.
According to phys.org
