Prepare to embark on a captivating journey into the mysteries of the cosmos!
The Enigma of 3I/ATLAS Unveiled
A recent study has shed light on the interstellar object 3I/ATLAS, revealing intriguing details captured by the Keck II telescope in Hawaii. On August 24, 2025, when 3I/ATLAS was at a distance of 2.75 times the Earth-Sun separation from the Sun and 2.6 times from Earth, the Keck Cosmic Web Imager (KCWI) captured an image that has left astronomers puzzled.
A Tale of Nickel and Cyanide
Unlike any known comet, including the interstellar comet 2I/Borisov, the gas plume surrounding 3I/ATLAS exhibits a unique spectrum. It showcases prominent nickel emission but lacks any signs of iron. This anomaly is typically associated with industrially produced nickel alloys, created through the carbonyl chemical pathway. The authors of the study propose that this natural process occurs near the nucleus of 3I/ATLAS, leading to the concentration of nickel as predicted by the formation and decomposition of nickel tetracarbonyl, Ni(CO)4.
A KCWI image reveals a central concentration of nickel relative to cyanide, with emissions extending to exponential radii of 600 kilometers for nickel and 840 kilometers for cyanide.
Anomalies and Asymmetry
The authors further highlight that the production rate of nickel relative to cyanide in 3I/ATLAS is significantly higher than in 2I/Borisov and far exceeds the median for solar system comets. The emission profiles of both nickel and cyanide are asymmetric, extending in the solar and anti-solar directions, providing clear evidence of an anti-tail. Surprisingly, the white light image of 3I/ATLAS lacks the familiar cometary tail typically expected for dust particles pushed away from the Sun by solar radiation pressure.
The Outlier Object
These new findings add to the growing list of anomalies associated with 3I/ATLAS, further solidifying its status as an outlier. When considering the previous seven anomalies (summarized here), 3I/ATLAS maintains its ranking of 4 on the Loeb scale.
Unveiling the Glow
We eagerly await the public release of images captured by the HiRISE camera onboard the Mars Reconnaissance Orbiter on October 2, 2025. These images will provide a side view of the glow surrounding 3I/ATLAS as it passed within 30 million kilometers of Mars, offering a resolution three times better than our current best images from the Keck and Hubble telescopes. Additional data is expected from the Juice and Juno spacecraft in November 2025 and March 2026, respectively.
The Thrill of Scientific Discovery
As we gather more high-quality data, the nature of 3I/ATLAS becomes increasingly clear. Science captivates us by allowing us to uncover new knowledge through evidence collected by instruments, rather than relying on stories passed down by people.
About the Author
Avi Loeb, a renowned figure in the field of astronomy, is the head of the Galileo Project and the founding director of Harvard University's Black Hole Initiative. He has held various prestigious positions, including the directorship of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics and the chair of the astronomy department at Harvard University from 2011 to 2020. Loeb's expertise extends beyond academia, as he has served as a member of the President's Council of Advisors on Science and Technology and chaired the Board on Physics and Astronomy of the National Academies. He is the bestselling author of "Extraterrestrial: The First Sign of Intelligent Life Beyond Earth" and a co-author of the textbook "Life in the Cosmos." His latest book, "Interstellar," was published in paperback in August 2024.
