Interstellar Comet 3I/Atlas Displays Unexpected Activity, captivating Astronomers
A newly discovered interstellar object, 3I/Atlas, is baffling scientists with an unusually high level of activity as it journeys through our solar system, marking the first time such behaviour has been observed in an interstellar comet. The object, only the third interstellar visitor detected to date after ‘Oumuamua and 2I/Borisov, is offering a unique opportunity to study the building blocks of planetary systems beyond our own.
Named for the Atlas observatory that first identified it, 3I/Atlas originates from outside our solar system, evidenced by its hyperbolic orbit – a trajectory indicating it was expelled from another star system before entering our region of space. Astronomers believe it might potentially be a fragment of a comet or asteroid formed around a distant star, providing a natural sample of materials from another world.
“Studying it allows us to know the history of other solar systems,” explains research highlighting the importance of analyzing its composition and movement to compare our solar system with others and better understand planet formation and evolution throughout the galaxy.
Currently traversing the solar system, 3I/Atlas will reach its closest approach to the Sun on October 29-30, 2025, at a distance of approximately 1.4 Astronomical Units (AU) – just within the orbit of Mars. It will pass near Mars on October 3, 2025, at a distance of roughly 0.19 AU.
Despite its close approach, 3I/Atlas poses no threat to Earth, with its closest approach to our planet expected on December 19, 2025, at a distance of approximately 1.8 AU.
The comet is currently traveling at speeds exceeding 58 kilometers per second (over 200,000 kilometers per hour) when far from the Sun, accelerating to around 68 kilometers per second as it nears our star. Recent observations have revealed the progress of a coma – the cloud of dust and gas surrounding the nucleus – and a tail, indicating important activity as it heats up.
This unexpected level of activity is what sets 3I/Atlas apart. Scientists are eager to continue observing the comet as it continues its journey through the solar system, hoping to unlock further secrets about its origins and the nature of interstellar objects.