Latest photo of interstellar comet 3I/ATLAS suggests that it might be changing its colour as it journeys through our solar system, Space.com reported. Astrophotographers Michael Jager and Gerald Rhemann captured the comet over Namibia during the recent total lunar eclipse, with images suggesting a surprising change in its colour. It glowed green.
The transformation is likely linked to the comet's increasing proximity to the sun. The greenish hue could also be the result of chemicals emitted from the comet as it gets closer to the Sun, possibly due to dicarbon (diatomic carbon) or even cyanide detected in its coma. However, further investigation is required to know the exact reason.
In a blog post on Tuesday, Harvard astrophysicist and 3I/ATLAS tracker Avi Loeb wrote: "The transition from red to green-blue colors might be associated with the steep rise in the production of cyanide (CN) as reported by the Very Large Telescope on August 25, 2025 (here)."
"The production of both cyanide and nickel without iron was found to increase dramatically with decreasing heliocentric distance to the power of about 9 (+/-1)."
Is It An Alien Tech?
3I/ATLAS was discovered on July 1 by the Asteroid Terrestrial-impact Last Alert System (ATLAS) at a distance of 675 million kilometres from the Sun. It is the third known object ever discovered coming from outside our solar system, the other two are - 1I/'Oumuamua, discovered in 2017, and 2I/Borisov, discovered in 2019.
Initially, some experts claimed that it's an alien technology. However, NASA explained that the object has been categorised as interstellar because of the hyperbolic shape of its orbital path. It does not follow a closed orbital path about the Sun.
The space agency has also stated that the comet poses no threat to Earth, and it is simply passing through our solar system and will continue its journey into interstellar space.
