What will happen when the Andromeda Galaxy and the Milky Way collide?

Scientists believe that when our galaxy, the Milky Way collides with the Andromeda Galaxy, a massive explosion will occur and both galaxies will not survive.

Scientists revealed that between four billion and five billion years from now, our galaxy, the Milky Way will collide with one of our large spiralled neighbours, the Andromeda Galaxy. When the collision happens, the galaxies, as we know them, will not survive.

As a matter of fact, our solar system is going to outlive our galaxy. Once the collision happens, the sun will not yet be a red giant star, instead, it will have grown bright enough to burn Earth’s surface. This means that no form of life will be able to survive on Earth.

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

Presently, the Milky War and the Andromeda Galaxy are approximately 2.5 million light years apart. However, the two galaxies are hurling towards one another at nearly 402,000 kilometres per hour, but even at this speed, they will not meet for another four billion years.

In four billion years, the galaxies will collide head-on and fly through one another. They will leave gassy, starry tendrils in their wakes. For eons, they will continue to come together and fly apart, jumbling stars and redrawing constellations. Eventually, after a billion or so years have passed, the two galaxies will merge. The solar system will then have a new cosmic address – a giant elliptical galaxy. The new galaxy will be formed by the collision and merger of the Andromeda Galaxy and the Milky Way.

It is believed that the collision of the galaxies has already started. Scientists have revealed that the faint halos of the galaxies have started to touch one another. Thus, in a manner of speaking, the collision between the Milky Way and the Andromeda Galaxy has already started.

Not taking the halo in account, the majority of the Andromeda Galaxy is approximately 2.5 million light years away from us. However, it is moving closer every day. It is important to note that as the galaxy comes closer, it will appear larger in our sky. People will thus be able to see it in the sky in the future.