Overview
- December 8–15 SPHEREx imaging and spectrophotometry detected strong emissions from CN, H2O, C‑H organics, CO2, and CO that were largely absent or weak before perihelion.
- Water and carbon monoxide fluxes rose by about 20 times relative to August measurements, while CO2 increased roughly 33 percent, lifting the CO-to-CO2 ratio about 15-fold.
- SPHEREx resolved gas comae roughly 1 to 3 arcminutes across, with round morphologies for H2O, CO2, and CO, contrasted by pear-shaped dust and organics pointing sunward.
- The differing shapes indicate CN and C‑H species originate from dust, whereas H2O, CO2, and CO are emitted from a symmetric region centered on the nucleus.
- The study, submitted to Research Notes of the AAS and posted on arXiv (2601.06759), reports a post-perihelion composition resembling typical solar‑system comets and notes a follow‑up SPHEREx pass planned for April 2026.