Overview
- A team led by the Virtual Telescope Project reported on November 11 an ionic tail at least 0.7 degrees long plus a detectable anti‑tail, with the tail length estimated at roughly three million kilometers.
- The interstellar visitor is traveling at about 60–61 km/s on a hyperbolic path and is expected to make its closest pass to Earth on December 19 at roughly 270 million kilometers before exiting the Solar System.
- Spectroscopy from ESO’s VLT and NOIRLab found familiar comet molecules including water, CO, methane and HCN, and MeerKAT detected OH radio lines consistent with water, with no evidence of artificial propulsion.
- Scientists are examining atypical traits such as elevated CO2 relative to water and non‑gravitational acceleration, with a leading hypothesis that long‑term galactic cosmic rays chemically processed the object’s surface.
- Separately, C/2025 V1 (Borisov) was discovered by Gennadiy Borisov in early November and passed about 103 million kilometers from Earth on November 11, with analyses indicating a likely Oort‑cloud origin distinct from 3I/ATLAS.