Overview
- NASA and international teams classify 3I/ATLAS as the third confirmed interstellar object, following ʻOumuamua and 2I/Borisov.
- The comet is on a hyperbolic trajectory at roughly 58 km/s and will reach perihelion on October 30 at about 1.4 AU from the Sun.
- It poses no threat to Earth, with closest approach near 1.8 AU, and will be unobservable near the Sun before emerging again early December.
- Spectroscopy, including from JWST, reports an atypically CO2‑rich mix of volatiles, while the bright coma leaves the nucleus size uncertain.
- A global campaign spans ground observatories, space telescopes, and Mars assets (Mars Express and Perseverance), as age analyses suggest extreme antiquity ranging from roughly 3 to more than 10 billion years.