Overview
- A Spanish-led team imaged powerful jets near perihelion and interprets the activity as cryovolcanism in a November 24 preprint.
- Spectral and photometric comparisons to pristine Antarctic carbonaceous chondrites indicate a metal‑bearing composition resembling trans‑Neptunian objects.
- Observers report a steady ~16.16‑hour brightness cycle that many attribute to rotation or periodic venting.
- NASA officials report no technosignatures and classify 3I/ATLAS as a natural interstellar comet, despite minority speculation such as a possible swarm producing an anti‑tail.
- The visitor will pass about 170 million miles from Earth on December 19, remains nonthreatening and too faint for naked‑eye viewing, and its nucleus size is still uncertain at roughly 1,400 feet to 3.5 miles.