Overview
- An arXiv preprint led by Josep Trigo‑Rodríguez reports gas‑and‑dust jets seen near the Oct. 29 perihelion using the Telescopio Joan Oró, interpreting them as active cryovolcanism; the findings are preliminary and not yet peer‑reviewed.
- ALMA measurements from August to October detected exceptionally high methanol and hydrogen cyanide, placing 3I/ATLAS among the most organic‑rich comets observed, though these organics are not evidence of life.
- NASA has updated its orbital model to lower the comet’s non‑gravitational acceleration, shifting a predicted March 2026 Jupiter pass to just outside the planet’s Hill sphere, with further refinements expected as outgassing is monitored.
- The comet will make its nearest approach to Earth on Dec. 19 at about 1.8 AU (roughly 270–274 million km), and NASA says it poses no threat and shows no signs of engineering or propulsion.
- Spectrophotometric analyses suggest a metal‑bearing, carbonaceous composition with similarities to transneptunian objects and an estimated age possibly older than the Solar System.