Galaxies that have formed no new stars in billions of years and have no gas left inside them are considered ‘red-and-dead.’ With the close examination of NGC 1277, we may have discovered the first such galaxy in our own cosmic backyard. (NASA, ESA, M. Beasley (Instituto de Astrofísica de Canarias), and P. Kehusmaa)

Astronomers Discover Exactly How Galaxies Die

With hundreds of billions of stars burning bright, ‘dead’ seems like a bit of an exaggeration. But every galaxy is headed for this fate, including ours.

As long as a galaxy is forming stars, it’s considered to be alive by astronomers.

The Trifid Nebula. located in the plane of the Milky Way, showcases a hotbed of young, newborn stars at its core. These stars form along high-density regions due to cool, collapsing gas clouds. (ESO / WFI / MPG / La Silla)

Our Milky Way contains large star-forming regions, mostly along its spiral arms, indicating stellar life.

The giant elliptical near the center of the Coma Cluster, NGC 4874 (at right), is typical of the largest, brightest galaxies found at the centers of the most massive galaxy clusters. Its stars are primarily older and redder, with only a few populations of bluer stars found sparsely inside. (ESA/Hubble & NASA)

But other, mostly elliptical galaxies, stopped forming stars many billions of years ago.

Arp 116, dominated by the giant elliptical Messier 60. Without large populations of gas to form new stars, the stars already existing within the galaxy will eventually burn out, leaving not very much that can illuminate the skies behind. (NASA/ESA Hubble Space Telescope)

These galaxies are called red-and-dead, because they don’t have any hot, young, blue stars associated with recent star formation.