During the merger, 100 trillion suns' worth of material collide, mix and ignite. [When Galaxies Collide: Photos of Great Galactic Crashes] And what's left after the fireworks?

The fireworks The force of gravity is enough to distort the shapes of galaxies as they encounter one another. But galaxies themselves are mostly (relatively) empty space.

Using their computer model, Cox and Loeb forecast that after the collision about 2 billion years from now, the Milky Way and Andromeda galaxies will be pulled together by gravity and blend into a ...

Earlier this year, NASA released a video simulation of what is likely to happen when both galaxies inevitably collide.

Gravity nudges galaxies toward one another—sometimes two, sometimes more—until they meet, their contents whooshing and mixing, and the slow-moving chaos molds them all into one big galactic ball.

The galaxies that formed those first super-massive black holes are still around, Kazantzidis added. "One of them is likely our neighbor in the Virgo Cluster, the elliptical galaxy M87," he said.

The researchers used recent observations from the Gaia and Hubble space telescopes to create a simulation where the Milky Way and Andromeda galaxies existed with a few other nearby galaxies.

Collide Planets & StarsEpic, mind blowing collisions of massive planetary bodies that leave behind molten craters.Create Your Own SystemsStart with a star, then add a planet.

What Happens When Galaxies Collide? In about four billion years from now, the Milky Way and Andromeda galaxies will crash together Visualization: NASA, ESA, and F. Summers, STScI Simulation credit ...

As they get closer, gravity pulls them even more, leading them on a path to collide. Photo Credit: NASA ...

Astrophysicist Paul Sutter details how galaxies collide, merge, and rip each other apart.

In about four billion years from now, the Milky Way and Andromeda galaxies will crash together Visualization: NASA, ESA, and F. Summers, STScI Simulation credit: NASA, ESA, G. Besla, Columbia ...