Mapping Metal and Molecule Mysteries in Interstellar Comet 3I/ATLAS
Hoogendam et al. (2025) used the Keck Cosmic Web Imager to study interstellar comet 3I/ATLAS, confirming gas emissions from cyanogen (CN) and nickel (Ni). They found Ni concentrated closer to the nucleus, suggesting it originates from short-lived compounds like metal carbonyls or organics. The findings indicate that interstellar comets may be metal-rich but water-poor, offering clues about the chemistry of distant planetary systems.
The Quiet Wanderer: Tracking Interstellar Comet 3I/ATLAS Before Its Solar Flyby
Comet 3I/ATLAS, the third known interstellar object, shows weak activity and reddening as it approaches the Sun. It spins every 16.16 hours and lacks a visible tail, likely due to geometry and low dust output. Despite its extrasolar origin, its properties resemble distant Solar System comets.
A New Visitor from the Stars: Studying Interstellar Comet 3I/ATLAS
Raúl de la Fuente Marcos and colleagues studied interstellar comet 3I/ATLAS, finding it has a dust-rich coma, a red D-type-like spectrum, and a 16.8-hour rotation period. Its properties resemble solar system comets, and its motion suggests it came from the galactic thin disk, likely from a Sun-like star system.
A First Glimpse of the Interstellar Comet 3I/ATLAS
Cyrielle Opitom and collaborators present early VLT/MUSE observations of the interstellar comet 3I/ATLAS, revealing a red, dusty coma but no detectable gas at 4.47 au from the Sun. Its color is redder than typical comets, resembling distant Solar System bodies. Future observations will track its activity and test predictions about its composition.
A New Visitor From Beyond: Discovery and First Look at 3I/ATLAS
Darryl Seligman and colleagues report the discovery of 3I/ATLAS, the third known interstellar object. Unlike ‘Oumuamua or Borisov, it shows weak activity, a flat light curve, and a moderately red color. Estimated to be ~10 km wide, it’s larger than Borisov and offers a new glimpse into interstellar diversity. The authors call for more observations to understand its nature before and after perihelion.