[Google AI Overview at the query, expanded ('AI Mode Conversation' is the expansion's header), signed out and incognito (operator defaults of 2026-10-01 and 2026-10-14). Received 2026-11-06 09:30 EST. The numbered citation links are Google redirects and are kept in the raw transcript; the source cards below the composition are listed in the cite list as pasted.] [QUERENT] 3i/atlas [SYSTEM] Comet 3I/ATLAS (also designated C/2025 N1) is the third confirmed interstellar object to pass through our solar system, following ʻOumuamua (2017) and Borisov (2019). [[1], [2], [3]] Key Facts & Characteristics * Discovery: Discovered on July 1, 2025, by the ATLAS survey telescope in Chile (with pre-discovery detections tracing back to mid-June 2025). [[1], [2]] * Origin & Age: Studies by telescopes including the [James Webb Space Telescope](https://www.google.com/goto?url=CAESYwHEIkXXGCvi6D9BjiALFrumBdHMgpMSVE4a7Y37ppRn40jC6a4y51xB8Iu5sbx50SLjTd_EyfZoEgk7y-bKneGRKvvuFcYly11RYROizsgbnYQ0f4PsH_f3LGnBUEHl2iOZGQ) indicate 3I/ATLAS may be 10 to 12 billion years old, making it a "galactic fossil" born during the universe's "cosmic noon"—long before our solar system formed ~4.6 billion years ago. [[1], [2]] * Orbit & Speed: It travels on a highly eccentric, unbound hyperbolic trajectory at speeds exceeding 221,000 to 246,000 km/h (approx. 68.3 km/s), exiting the solar system permanently after its passage. [[1], [2], [3]] * Close Approaches: It passed its closest approach to the Sun (perihelion) at about 1.35 to 1.4 AU on October 29–30, 2025, and its closest approach to Earth in December 2025 at a safe distance of ~1.8 AU (~270 million km / over 600 times the Earth-Moon distance). It poses no threat to Earth. [[1], [2], [3], [4]] * Composition & Activity: Unlike dry rocks like ʻOumuamua, 3I/ATLAS is an active, icy comet featuring a carbon-dioxide-rich coma, water vapor/ice, methane, methanol, and high levels of deuterium (heavy water), alongside a hard outer radiation crust cracked by solar heating. [[1], [2], [3], [4]] * Status: Extensive tracking by NASA, ESA (including the JUICE mission), Webb, Hubble, and radio arrays confirmed it is a natural comet, ruling out artificial or technological origin hypotheses. [[1], [2], [3], [4]] For official imagery, tracking updates, and research resources, visit [NASA Science - Comet 3I/ATLAS](https://www.google.com/goto?url=CAEScwHEIkXX8e9nLAIeNg15enHUGoSGNFl8aLPGvz28mc6yAWmvNIPVVQa3kNvBOLXF5xAlgj3l2obDPtoxd8MHoPh2pMtiVi6fIVbHynFP2ptFJ6cM1KP8rqInnCrfxE6pSBczRGjCLvWbngLA8AQ9hw1SXoE) or review the [ESA FAQ on 3I/ATLAS](https://www.google.com/goto?url=CAESnAEBxCJF1z5TMbUXHXo6SGWZJjpTCjYLRmEk4hSLZqS1xVzTO7OpUHrBOpeCXCnRBPaqsZzITwStiDkJfTw04eaYOpJSbDC1AnSh4Oo4yQ4MyyoO26Pb5MP2dxxsel6nDIw6OM9LEIDhFwIxj53JoAXk9Tk3bH0S3mtWdBSl3WktiUArf0G6labYp4LrkISCk8jh6tjL1Xm6S11rI34). [[1], [2]] If you'd like, I can share more details on: * Its chemical breakdown compared to local solar system comets * The specific spacecraft and telescopes that tracked it * The timeline of its outgassing and jet eruptions Wikipedia