Ripples found in the Milky Way’s disk reveal our galaxy survived an ancient hit-and-run. Now, astronomers might have caught the culprit.
A cosmic rabbit hole in the tail of Leo will take you to Abell 1367, a wonderland of galaxies more than 300 million light-years from Earth. Step in and lose yourself in the vastness.
Astronomers determine the number of galaxies in the universe by counting up the number visible in a tiny portion of the sky, and then accounting for all the regions of the observable universe. A 2013 study estimates that there are 225 billion galaxies in the observable universe.
The Great Hercules Cluster is on everyone's observing list this summer. But there's lots more to see within a stone's throw of this grand object — like 20 galaxies!
The Local Group galaxies and their kin are the building blocks of the most magnificent galaxies in the universe. Let them inspire your winter nights.
Here's how to hone your galaxy-hunting skills — and what to expect at the eyepiece.
Evidence from observations sheds doubt on cosmic cannibalism as a source for galaxy growth, suggesting that instead galaxies grow by pulling in gas from the intergalactic medium.
Astronomers have identified 53 “super spirals” — spiral galaxies that are huge and incredibly luminous — as part of a project exploring archived observations.