The comet 3I/ATLAS, our Solar System’s third confirmed visitor from interstellar space (after ʻOumuamua and Borisov), is putting on a spectacular show. Images captured after its closest approach to the Sun reveal a complex structure of multiple jets blasting out from the comet’s nucleus. This dramatic display makes it a prime target for further study by powerful telescopes like Hubble and Webb.
Discovered in July 2025 by NASA’s ATLAS (Asteroid Terrestrial-impact Last Alert System) survey telescope, 3I/ATLAS hurtled into our solar system from the direction of the Sagittarius constellation. Its highly elliptical orbit – considered “hyperbolic” due to its extreme eccentricity and speed – designated it as the most dynamically extreme object ever recorded.
Reaching perihelion (closest point to the Sun) on October 30, 2025, 3I/ATLAS skimmed just inside Mars’s orbit at a blazing speed of about 68 km/s. This proximity temporarily hid the comet from Earth-based telescopes, but soon after, it reappeared and began its journey back into interstellar space.
The first images taken after perihelion, on October 31, showcased a faint coma (fuzzy cloud surrounding the nucleus) but lacked visible jets. However, by November 8th, astronomers from the ICQ Comet Observations group captured striking images of at least seven jets emanating in various directions, some even forming anti-tails that point directly opposite to the comet’s motion.
These intricate jet structures raise intriguing questions about 3I/ATLAS’s composition and behavior. Harvard University Professor Avi Loeb highlights this anomaly: “Given that a large number of jets appear in many directions, the reported non-gravitational acceleration of 3I/ATLAS requires much more than 10-20% of its initial mass to have been ejected near perihelion,” he explains. “Only a fraction of that mass carries an excess momentum in a preferred direction.” This suggests a substantial portion of the comet’s material must be dispersed as debris, hinting at a unique composition compared to typical comets within our Solar System.
Further observations by a team from the British Astronomical Association (BAA) on November 9th revealed a long “smoking” tail and two prominent anti-tail jets, solidifying the case for this extraordinary jet activity.
The comet will make its closest approach to Earth on December 19th at a distance of approximately 269 million kilometers – roughly one hundred times the length of its jet structure. This proximity makes 3I/ATLAS an ideal target for detailed analysis by powerful telescopes like Hubble and Webb, promising valuable insights into this enigmatic interstellar visitor and its dynamic processes.
