Colliding Galaxies

The Milky Way and the Andromeda Galaxy are on a collision course. A computer model developed by scientists at the Museum shows that the pair is bound to crash in about three billion years and merge into a single elliptical galaxy. This video shows the result of that computer model, called a simulation.

More on this Visualization

Galaxies appear to exist in splendid isolation. But observations reveal that galaxies actually collide with one another quite frequently—perhaps many times in their lifetimes. Because galactic evolution takes place over billions of years, astronomers can only observe snapshots of different galaxies at different stages of their history—a bit like understanding how a child grows by looking only at a set of class pictures from different grades in a school. To understand how galaxies evolve, scientists use supercomputers to model galactic dynamics, including the fate of our own Milky Way Galaxy.

The Milky Way will collide with its nearest large neighbor, the Andromeda Galaxy, in three billion years. Using software from the Max Planck Institute for Astrophysics in Germany, students and scientists at the American Museum of Natural History computed how the stars, gas, and dark matter in the two galaxies will behave under the influence of gravity and gas pressure over the next six billion years. Sixty-four computer processors at the Pittsburgh Supercomputing Center crunched numbers around the clock for almost a month to simulate the collision. The result is shown in this video.

This interactive also uses data from the Digital Universe Project, a collaboration of NASA and the American Museum of Natural History, to create an accurate three-dimensional map of the visible Universe. The Digital Universe, which includes dozens of datasets that are constantly updated, is free to download.