3I/ATLAS (C/2019 Y4) — Photometric Anomaly 2025

Version 2.1 (October 2025) — Adds cross-validation test using the Zwicky Transient Facility (ZTF DR19) via IRSA TAP.No independent detections were found for 3I/ATLAS during July–October 2025, confirming MPC photometry as the sole observational record. Includes updated verification report and new OpenTimestamps proof (2025-10-30 v2.1). --- 🔖 Version Lineage Note This v2.1 release was derived from the GitHub-archived v2.0 record (https://doi.org/10.5281/zenodo.17484046) rather than the manually curated dataset version (https://doi.org/10.5281/zenodo.17483027). All files and metadata have been synchronized between both records. Both belong to the same concept DOI family (https://doi.org/10.5281/zenodo.17477597) and are fully interoperable for citations and reproducibility.