A visitor from deep space is racing through our solar system, and it is behaving so strangely that it's challenging everything we know about comets. This object, the third known interstellar visitor, is named 3I/ATLAS.
As it passed its closest point to the Sun (perihelion) on October 29, 2025, new data revealed shocking behaviour. It suddenly became five times brighter and, most perplexingly, it is showing non-gravitational acceleration. It's being pushed.
