Overview
- The third confirmed interstellar object enters its closest approach to the Sun, a phase when heating can intensify outgassing and even fracture some comets, though 3I/ATLAS is not observable from Earth during this interval.
- A not-yet peer-reviewed Keck-II analysis reports cyanide and nickel emissions both toward and away from the Sun, which some commentators, including Avi Loeb, cite as evidence for a sunward anti-tail.
- Most comet specialists stress natural explanations, noting 3I/ATLAS looks and behaves like a comet, with proposed mechanisms including large dust grains and rotation-driven ejection that can place material sunward.
- Observations to date indicate an unusually CO2‑rich coma with a CO2 to H2O ratio near 8:1, alongside a strongly hyperbolic trajectory and speeds around 58–60 km/s that confirm its interstellar origin.
- Further checks arrive soon with planned observation opportunities near Venus on November 3, near Earth on December 19, and near Jupiter around March 16, 2026, offering targets for missions such as ESA’s Juice and other assets.