Comet C/2025 K1 (ATLAS) survives close flyby of the Sun, turns rare golden

[Buster's Uncle]

Chron
Comet survives close flyby of the Sun, turns rare golden
Ariana Garcia
Tue, November 4, 2025 at 9:35 AM EST
2 min read



Amateur astronomer Dan Bartlett recently captured C/2025 K1 (ATLAS) from June Lake, Calif. He described it as having a red/brown/golden color. (Dan Bartlett)


Most comets are white, yellow, blue, and occasionally green-but a rare golden comet is now gracing the sky. Dubbed C/2025 K1 (ATLAS), the icy visitor was discovered in May 2025 by the Asteroid Terrestrial-impact Last Alert System. It's been tracked by astronomers, including amateur observer Dan Bartlett, who recently spotted it from June Lake, Calif. Other amateur astronomers have reported sightings from Payson, Ariz., and Ballico, Calif.

"This comet was not supposed to survive its Oct 8th perihelion (0.33 AU)," Bartlett told SpaceWeather.com. "But it did survive, and now it is displaying a red/brown/golden color rarely seen in comets." Its closest approach to Earth will be on Nov. 25, 2025, at a distance of about 0.40 AU.

The dynamically new comet comes directly from the Oort Cloud, a distant, spherical shell of icy bodies at the edge of the solar system. Spectroscopy by David Schleicher of the Lowell Observatory shows the comet lacks the carbon compounds normally found in these visitors. "All of the carbon-bearing species, including CN, are unusually low," he wrote in The Astronomer's Telegram #17362.

Usually, sunlight makes cometary gases glow green from diatomic carbon (C2) or blue from ionized carbon monoxide (CO+). With these colors missing, the comet now appears golden. Scientists aren't sure whether the unusual hue is related to its close encounter with the Sun.



Comet C/2021 (ATLAS), on the left, was spotted flying next to the brighter C/2025 (SWAN) back in September. (Luc Perrot (TWAN))


Bartlett said the comet is fairly bright at 9th magnitude, making it accessible with backyard telescopes. In September, NASA shared an image of the comet while it appeared fainter and green, flying near C/2025 R2 SWAN.

Observers in the northern hemisphere can spot the comet shortly before sunrise near the boundary of Virgo and Leo.

https://www.yahoo.com/news/articles/comet-survives-close-flyby-sun-143510572.html