The sheer speed is almost incomprehensible — a celestial bullet hurtling through the vacuum of space, carrying secrets from a star system light-years away. This is not a local inhabitant of our solar system, but an alien traveller: the interstellar comet, 3I/ATLAS. For months, astronomers, engineers, and space agencies have been gripped by this rare visitor, which is now making its final, spectacular pass before disappearing back into the abyss from which it came.
Discovered in late June and confirmed in July as only the third known interstellar object ever spotted, 3I/ATLAS has spent recent months racing through our planetary neighbourhood at a staggering 210,000 kilometres per hour (130,000 mph). After successfully navigating close encounters with Mars and the sun in October, the comet is preparing for its most significant moment for us Earthlings: its closest approach to our planet on Dec. 19.
