Overview
- Solar-monitoring spacecraft tracked an unusually steep surge in brightness through the Oct. 29 perihelion, with analyses by Qicheng Zhang and Karl Battams using SOHO, STEREO-A and GOES-19.
- The object appeared distinctly blue, signaling a glow dominated by gaseous emissions rather than the dust-reflected light typical of many comets.
- NASA and most astronomers characterize 3I/ATLAS as a natural interstellar comet with no threat to Earth, which it will pass at roughly 267–270 million kilometers on Dec. 19.
- High-resolution HiRISE images taken by Mars Reconnaissance Orbiter on Oct. 2–3 have not been released, with NASA citing delays from a partial U.S. government shutdown.
- Radio searches have reported no transmitter signals even as Avi Loeb publicizes a technological-artifact hypothesis that remains outside the scientific consensus.