Mars. From forming black holes to phantom dark energy, discover the cosmic mysteries astronomers uncovered last year.

Learn about the 3I/ATLAS mystery as Harvard's Avi Loeb reveals 'wobbling jets' that could suggest the interstellar visitor is ...

I do so love an ostentatious comet. As I wrote in a recent “The Universe” column, when these dusty ice balls are billions of kilometers from the sun, they’re frozen solid. But as they near our star on ...

While online conspiracies swirl, comet 3I/ATLAS made a close pass by Earth on Dec. 19, giving astronomers a rare glimpse of a ...

A comet known as 3I/ATLAS made news earlier in July when it was confirmed to have originated outside of Earth's solar system. But is 3I/ATLAS definitely an icy comet? A trio of researchers that most ...

Scientists have sought out and detected radio emissions from from interstellar comet 3I/ATLAS, all but confirming that it has natural origins.

A small, icy visitor from beyond the solar system is giving scientists an unusually close look at the chemistry that may help planets come alive. As the interstellar comet 3I/ATLAS sweeps past the Sun ...

NASA's alien-hunting Europa Clipper spacecraft took seven hours of ultraviolet observations of interstellar comet 3I/ATLAS while both objects zoom toward Jupiter.

In the vast, silent theatre of the cosmos, a rare visitor is preparing for its final bow before departing our solar system forever. The interstellar object known as 3I/ATLAS — the third confirmed ...

I/ATLAS has passed its closest point to Earth, meaning we will soon lose sight of it for good. Some scientists want to send a spacecraft to chase down the alien comet — or the next interstellar object ...