On July 1, 2024, astronomers spotted something extraordinary: a massive object, now called 3I/ATLAS, hurtling into our Solar System at over 133,000 miles per hour. It’s not looping around the Sun like a comet—it’s just passing through.

That’s how we know: it’s interstellar.

Only two other objects like this have ever been confirmed—ʻOumuamua in 2017 and Comet Borisov in 2019.

3I/ATLAS may be up to 12 miles wide, icy like a comet, and blazing a one-way path from deep space. 

Scientists don’t know exactly where it came from, or what pushed it in our direction. For now, it remains a mystery from another star system, making a rare and fleeting visit.