Milky Way To Collide With Its Largest Neighbour Andromeda? What New Study Said

Astronomers have long believed that the Milky Way galaxy may collide head-on with its largest neighbour, the Andromeda galaxy, in about 4.5 billion years. But a new study shows the cosmic clash, named Milkomeda, might not happen the way it was thought.

The new data, obtained using the Hubble and Gaia space telescopes, indicates the likelihood of the Milky Way and Andromeda colliding within the next 4 to 5 billion years is only 2 per cent, CNN reported.

It also says there is a roughly 50 per cent chance they will collide at some point in the next 10 billion years.

Earlier, scientists believed the collision may destroy both galaxies, merging them into an elongated one. The reason was that the two galaxies were moving toward each other at 2,24,000 miles per hour. They expected it to be similar to other galaxy collisions where a merger would create cosmic fireworks. 

Carlos Frenk, a Professor at Durham University in England and study co-author, said, "Until now we thought this was the fate that awaited our Milky Way galaxy. We now know that there is a very good chance that we may avoid that scary destiny".

Dr Till Sawala, astronomer at the University of Helsinki in Finland and the lead author of the study, said the merger may create a strong starburst where many new stars would form. After that, many young stars will explode, and the supermassive black hole at the centre will become very active, sending out a lot of radiation, he said. 

A few billion years after the merger, the two original galaxies will no longer look like they used to; instead, they will turn into one spiral-shaped galaxy called an elliptical galaxy, said Mr Sawala.

Our corner of the universe, called the Local Group, consists of 100 other smaller galaxies, including some large ones like the Large Magellanic Cloud (LMC) and the Triangulum Galaxy. M33 is an Andromeda satellite, whereas the LMC orbits the Milky Way.

Mr Frenk cautions that the Milky Way is more likely to collide with the LMC in the next 2 billion years, which might drastically alter our galaxy.

Mr Sawala said, "The extra mass of Andromeda's satellite galaxy M33 pulls the Milky Way a little bit more towards it."

According to Geraint Lewis, an astrophysics professor at the Institute for Astronomy at the University of Sydney, scientists are unsure whether the Milky Way and Andromeda will collide, but even if they do, the gravitational pull that each will exert on the other is likely to leave the two massive galaxies in an awful situation.