In four billion years, our galaxy, the Milky Way, will collide with our neighbouring great spiral, Andromeda.
Galaxies as we know them will not survive.
Our solar system will live longer than our galaxy. When fusion occurs, the Sun will not yet be a giant red ball, but it will have grown big enough to fry the Earth’s surface. The life forms that will still be living there will be treated to a particularly remarkable cosmic spectacle.
Nowadays, Andromeda is about 2.5 million light years away from the Milky Way. Attracted by gravity, the two galaxies collide at a speed of 402,000 km/hour. Even at this speed, it will take 4 billion years for them to meet. The two galaxies will collide head-on before crossing each other, leaving behind them trails of gas and stars.