One year ago, on July 1 2025, astronomers discovered a fascinating new object moving through the Solar System. Detected by the Asteroid Terrestrial-impact Last Alert System (ATLAS), the object was quickly recognised as something special.
Tearing past at record speed, the comet, known as 3I/ATLAS, is only the third interstellar object ever detected. Born around another star, it was a fleeting visitor that is now heading out of the Solar System at more than 60 kilometres per second, never to return.
