How do we know 3I/ATLAS, also called comet C/2025 N1 (ATLAS), is interstellar? Will it strike Earth? Can we visit it? Here are all of your questions answered.

On July 1, 2025, a telescope in Chile detected something unexpected: a faint object streaking across the sky at an unusual speed and angle. Within hours, astronomers realized what they were seeing. This wasn’t a comet from the outer reaches of our own solar system,

Late in the evening on July 1, a telescope in Chile that is part of the global, NASA-funded Asteroid Terrestrial-Impact Last Alert System (ATLAS) picked up on a new moving dot in the sky, an object traveling past the orbit of Jupiter.