What would happen to Earth if Andromeda collided with our galaxy right now?

NASA, ESA, Z. Levay and R. van der Marel (STScI), T. Hallas, and A. Mellinger

The end of the Milky Way will be inevitable. Andromeda is heading towards it on a collision course at 110 kilometers per second .

Andromeda is the farthest object that the human eye can grasp. Located 2.5 million light-years from Earth, during a clear, moonless night it is possible to observe it as a faint glow, a product of gas from the billions of stars that inhabit this galaxy.

And although at first glance the distance between Andromeda and the Milky Way seems insurmountable, both galaxies attract each other at a speed of 110 kilometers per second, a trend that will continue for the next 4 billion years, when they merge into a inevitable clash that will shape a new galaxy.

Astronomers believe that most stars and solar systems in both galaxies will survive the merger due to the distance that separates them; however, the event will ultimately change the structure of the Local Group, the cosmic neighborhood of approximately 30 nearby galaxies to which we belong.

Andromeda approaches the Milky Way for the next 2 billion years, enough for its disk to become the most massive object in the night sky.

From then until the next 3.7 billion years, Andromeda reaches its maximum size before beginning to merge with our galaxy in the next 20 million years, as the sky is covered with the formation of new stars.

After reaching 4 billion years, both galaxies lose their characteristic shape and as Andromeda stretches further and further, the luminous center of the Milky Way visible from Earth begins to warp.

In 5 billion years, the nuclei of the two galaxies will look like a pair of bright lobes and then the final part of their merger will begin, a phenomenon that will last another 2 billion years, resulting in a huge elliptical galaxy. which some astronomers call Lactomeda.

And although the animation and the NASA images that give it shape illustrate the terrestrial point of view with mountains that accompany the night sky, by then the Earth will be a sea of lava and life on our planet will have disappeared due to the increase in the luminosity of the Sun, which will form a red giant star, devouring all the inner planets of the Solar System.