Overview

• An MDM Observatory preprint reports the onset of faint CN emission between August 8 and 17, measuring a CN production rate of about 8×10^23 s⁻¹ and finding an exceptionally low C2-to-CN ratio that places 3I/ATLAS among the most carbon‑chain depleted comets observed.
• Simultaneous photometry in the same campaign shows modest growth in the coma and low gas‑to‑dust output, consistent with relatively weak gas-driven activity at 3.2–2.9 au.
• Previous space‑based spectra from JWST and SPHEREx indicate a CO2‑dominated coma, strengthening evidence that the object’s activity is driven by low‑temperature volatiles rather than water.
• Deep imaging from Gemini South documents a developing coma and an anti‑solar tail, confirming active, comet‑like behavior on a hyperbolic path through the Solar System.
• A new technosignature‑search framework urges routine checks of interstellar visitors, and a separate archival analysis suggests TESS imaged 3I/ATLAS in May 2024 to extend its trajectory, though both efforts await further confirmation.