Two newly discovered comets are streaking across the sky in a spectacular display as they make their closest approaches to Earth this month. Comets are made of ice, frozen gases and rock, and as they ...

Editor's note, Dec. 19 at 10:00 a.m. ET: Comet 3I/ATLAS officially passed its closest point to Earth last night and is zooming away from us for good. However, due to rainy conditions in Italy, the ...

A comet from another star system is due to make its closest—and final—approach to Earth this week before it continues on its journey back toward interstellar space. Interstellar Comet 3I/ATLAS will ...

Interstellar comet 3I/ATLAS made its closest approach to Earth on Friday, Dec. 19. The comet will pass within about 170 million miles of our planet and poses no danger. While not visible to the naked ...