The biggest objects in the universe are clusters of galaxies, such as the supercluster we live in right now - and including Abell 370, which was captured in a sprawling glittery space-scape by the ...

An object spotted with help of citizen scientists was moving so fast through the Milky Way that it could escape the gravity of the galaxy and reach intergalactic space, new research has found. Likely ...

An interstellar object named 3I/ATLAS, confirmed to be a comet, is passing through Earth's solar system. The comet poses no threat to Earth and will make its closest approach to our planet on Dec. 19.

The Haleakala Observatory, left, houses one telescope for the ATLAS system. That system first spotted the object 3I/ATLAS, which isn’t visible in this image. AP Photo/Lindsey Wasson Current ...

Just the third-ever confirmed interstellar object has been detected in our solar system. Here's what we know. (Spoiler: It's not aliens.) The interstellar comet, originally called A11pl3Z and now ...

Washington — Members of Congress heard stunning testimony during a hearing July 27 with a former intelligence officer-turned-whistleblower and two pilots about their experiences with strange, ...