Overview
- Integral-field spectra from Keck/KCWI on August 24 resolve strong nickel and cyanide emissions with no detectable iron, with nickel concentrated within roughly 600 km of the nucleus and cyanide extending to about 840 km.
- The object has developed a sunward anti-tail confirmed in the Keck dataset after earlier Hubble hints, while white-light images still lack a classic dust tail.
- JWST measurements indicate a CO2-dominated coma of about 87% CO2, 9% CO, and 4% H2O, and Swift ultraviolet OH detections imply water production near 40 kg per second.
- ESA’s Hera is projected to traverse the ion-tail region October 25–November 1 without in-situ sensors, and NASA’s Europa Clipper could attempt sampling October 30–November 6 if solar wind conditions permit, near the October 29 perihelion.
- HiRISE images from NASA’s Mars Reconnaissance Orbiter taken during the early-October pass have not been released publicly, and most researchers still assess 3I/ATLAS as a natural but unusual comet despite public speculative claims.