Particle.news
Download on the App Store

SPHEREx Detects 20-Fold Post-Perihelion Surge in Interstellar Comet 3I/ATLAS

Radio campaigns report no technosignatures from the object.

Overview

  • A NASA SPHEREx analysis led by Michael Werner finds up to roughly 20 times more water, CO, CO₂ and organic volatiles released after the Oct. 29, 2025 perihelion.
  • The comet appeared comparatively quiet before perihelion, then became far more active as solar heating reached deeper ices in the nucleus.
  • Breakthrough Listen observations with the Allen Telescope Array, MeerKAT and the Green Bank Telescope reported no artificial radio emissions.
  • Earlier observations, including Hubble, indicated a CO₂‑dominated coma and unusual dust behavior, with changing jets and a sunward anti‑tail.
  • Scientists are tracking a March 2026 approach to Jupiter that could perturb its trajectory as the rare interstellar visitor continues outbound.