What will happen when the Milky Way and Andromeda meet?

The meeting between the Milky Way and Andromeda will begin in 4 billion years and will reach its last point 2 billion years later. Scientists agree that at the end of this process, a new galaxy will emerge very different from the current ones: elliptical and non-spiral

Two billion years ago, an intergalactic conflict changed the spatial order forever. They found Andromeda and M32P, two of the largest and most powerful galaxies of the local group, the system in which the Milky Way, the sun, the planet Earth and the human species also coexist. In the collision, Andromeda devoured his companion M32P, and became a spiral galaxy with a diameter of one hundred and fifty thousand light years between the ends of his arms: the giant galaxy closest to the Earth.

Part of a survey conducted by a group of scientists from the University of Michigan (USA) was published last week in the journal Nature Astronomy. (Read also: The universe expands and the galaxies separate)

According to the results of the study, a group of extremely compact stars, observed in the vicinity of # Andromeda, is considered one of the densest places in the world. the universe, is not a small independent galaxy but the core of the M32P off.

"This kind of satellite galaxy we called M32 is actually the nucleus of the galaxy trapped by Andromeda," El Pais de España Eric Bell, a researcher at the University of Michigan and co-author, told El Pais de España newspaper. of the book. He added: "It's amazing to know that our galaxy had a big parent of whom we had never known anything." (You may also be interested: Discovered for the first time a galaxy without dark matter)

In addition to revealing the consequences of the fatal encounter between the two galaxies, US scientists have confirmed what the images of the Hubble telescope and the mathematical models had already predicted: In about 4 billion years, there will be a new conflict within the local group. This time, the protagonists will be Andromeda and the Milky Way.

However, despite what we thought a few years ago, there will be no direct collision between the two. Andromeda does not eat the Milky Way. The meeting will be more peaceful than expected. A kind of harmonic fusion without too many consequences for the solar system. This is confirmed by the results of the European Gaia mission, published in February this year.

The meeting between the Milky Way and Andromeda will begin in 4 billion years and will reach its last point 2 billion years later. Scientists agree that at the end of this process, a new galaxy will emerge very different from the current ones: elliptical and non-spiral like the Milky Way and Andromeda.

Everything seems to indicate that the reason why the shock between the two galaxies will not be so traumatic that in each there are stars and planets separated from each other by thousands of light-years. This distance reduces the density and the magnitude of the impact. The sun will not run any risk during the merger, but it should change places. For the moment, the two galaxies will continue to approach at an average speed of 300 kilometers per second.