Deep-Space Photos: Hubble's Greatest Hits

The Hubble Telescopes Greatest Hits
The legendary space telescope celebrates its 20th year in orbit
NASA

Antennae Galaxies
Approximately 500 years ago, two galaxies collided together to form the Antennae galaxies in the constellation Corvus. They are the nearest and youngest example of galaxies fusing together to form what astronomers call interacting galaxies. In this process, billions of stars and star clusters are formed.

Get the Latest Photos from Time.com
Get TIME photos and pictures of the week delivered directly to your inbox.