It seems that our solar system is becoming a popular destination for visitors from other star systems. Astronomers have possibly identified a third interstellar object, indicating it originates beyond our solar system. The initial interstellar object was ‘Oumuamua, discovered in 2017, followed by a comet called 2I Borisov.
This newly discovered object, named 3I/ATLAS or C/2025 N1 (ATLAS) by the International Astronomical Union’s Minor Planet Center, was spotted using a survey telescope known as the Asteroid Terrestrial-impact Last Alert System (ATLAS), designed as an early warning system for asteroid impacts. 3I/ATLAS is not considered a threat to Earth.
According to Paul Weigert, a professor at Western University, the observation data suggests that 3I/ATLAS has an interstellar orbit, moving too swiftly to be bound to the sun, indicating it likely originated from outside our solar system. Initially thought to be an asteroid, ‘Oumuamua was later confirmed to be a comet, as was 2I Borisov. Recent observations of 3I/ATLAS have shown signs of a tail, further supporting its classification as a comet.
The object’s eccentricity is a key indicator that it hails from beyond our solar system. While periodic comets typically have eccentricities between 0.2 and 0.7, those exceeding one are considered hyperbolic comets originating from the Oort Cloud, a region surrounding our solar system containing icy objects. High eccentricities, like the estimated six for 3I/ATLAS, suggest an object from outside our solar system.
3I/ATLAS is currently beyond Mars’ orbit and will approach its closest point in October before heading out of the solar system. Initial estimates suggest it may be around 10 kilometers in size, making it the largest of the three observed interstellar visitors so far. Despite the mystery surrounding such interstellar objects, astronomers have not observed any unusual behavior in 3I/ATLAS.
As major telescopes focus on studying 3I/ATLAS, the new Vera C. Rubin Observatory in Chile has begun operations, expected to detect several similar objects annually. The increased discovery of these interstellar visitors is attributed to advancements in telescope technology, allowing for deeper surveys of space around us.
For researchers like Weigert, who specialize in asteroids and comets, the opportunity to study these objects up close is a thrilling prospect. The ongoing exploration of these interstellar visitors offers a fascinating glimpse into the distant realms of our universe.
