Gemini North Images Show Faint Green Glow From Interstellar Comet 3I/ATLAS

Overview

• NSF NOIRLab released Gemini North observations recorded on November 26 at Maunakea that reveal a subtle green tint around 3I/ATLAS.
• The latest view contrasts with earlier Chilean images that appeared reddish after the comet emerged from behind the Sun near the star system Zaniah in Virgo.
• The color shift is linked to light emitted by gases in the coma as they warm and sublimate, with diatomic carbon identified as a key contributor.
• 3I/ATLAS is only the third interstellar visitor observed in our Solar System, following 1I/‘Oumuamua in 2017 and 2I/Borisov in 2019.
• The observing session ran through NOIRLab’s Shadow the Scientists program led by Bryce Bolin, and Gemini teams plan continued monitoring to track any compositional changes or eruptive activity as the object cools and departs.