3I/ATLAS Photometric–Chromatic Anomaly (2025) 3I/ATLAS

3I/ATLAS (C/2025 N1): Photometric–Chromatic Anomaly Analysis, Interstellar Anomaly Index, Δv-Based Dynamical Assessment, and Extended Post-Perihelion Evolution (Version 2.5) This archive contains the complete v2.5 research dataset, analysis scripts, figures, LaTeX source, and cryptographic authenticity proofs associated with the study of the interstellar object 3I/ATLAS (C/2025 N1).Version 2.5 represents the most detailed and reproducible photometric, chromatic, dynamical, and anomaly-index analysis available to date. The dataset incorporates: 🔭 Photometric & Chromatic Diagnostics MPC photometry (May–Nov 2025) Multi-filter colour indices (g–o, g–r, r–o) Solar-referenced colour deltas Optical acceleration time series with pre- and post-perihelion spikes Post-perihelion fading extension to 2025-11-21 📈 New Dynamical Analysis (Δv Scaling & Jupiter Encounter Geometry) Version 2.5 introduces a quantitative dynamical test of the optical-acceleration anomaly, converting the measured proxy into two calibrated non-gravitational impulses: 8 m/s minimal Δv — the value required to reproduce the~1×10⁵ km lateral offset invoked in Loeb’s Jupiter near–Hill-radius geometry 25 m/s photometric-inferred Δv — consistent with the fitted A₁ parameter Both scalings show that two short-lived activity spikes (10 Sept and 2 Oct 2025) account for >90% of the total impulse.The Δv is sufficient to produce the course deviation required for Loeb’s scenario, whether interpreted as natural activity or a non-standard process. 📊 Interstellar Anomaly Index (IAI) Version 2.5 formalises the Interstellar Anomaly Index, a four-component metric measuring: Photometric anomaly Chromatic anomaly Dynamical anomaly Morphological anomaly 3I/ATLAS obtains IAI ≈ 0.95, placing it at the extreme end of known interstellar visitors and distinctly separated from JFCs, LPCs, and 1I/ʻOumuamua / 2I/Borisov in (e, IAI) space. 📘 Manuscript The full LaTeX source and compiled PDF of“3I/ATLAS (C/2025 N1): Photometric–Chromatic Anomaly, Δv Geometry, and Interstellar Anomaly Index”are included. 🔐 Cryptographic Proofs All analysis files, scripts, and outputs are authenticated via: SHA-256 digests GPG signatures OpenTimestamps proofs anchored on the Bitcoin blockchain A reproducible “protect & seal” pipeline Ensuring full forensic reproducibility of the analysis chain.