Galactic cannibalism – The Collision of Galaxies!

Galactic cannibalism refers to the process in which a large galaxy, through tidal gravitational interactions with a companion, merges with that companion; that results in a larger, often irregular galaxy.

The most common result of the gravitational merger between two or more galaxies is an irregular galaxy, but elliptical galaxies may also result.

It has been suggested that galactic cannibalism is currently occurring between the Milky Way and the Large and Small Magellanic Clouds. Streams of gravitationally-attracted hydrogen arcing from these dwarf galaxies to the Milky Way is taken as evidence for the theory.

Galactic interactions are a common occurrence as the universe evolves. The Hubble Space Telescope has imaged a number of such interactions. Most galaxies will merge with others in their lifetimes and there’s substantial evidence to indicate both systems have joined up with others over the eons.

In around two billion years, Andromeda and the Milky Way will fly past each other, setting the process in motion.

The fly-by will drag out a long tail of stars from each of the galaxies before the two whip back around and mash together, forming one bulbous elliptical galaxy instead of the classic spiral form both now have. The resulting galaxy will dwarf the dozens of others in our cosmic neighborhood.

The chances of a collision with Proxima Centari, the sun’s closest neighbor, are remote because of the vast distances involved. The star is more than four light years away.