{"paper":{"title":"Proxima Centauri b is not a transiting exoplanet","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.IM","astro-ph.SR"],"primary_cat":"astro-ph.EP","authors_text":"Aviv Ofir, Cristina Rodr\\'iguez-L\\'opez, David Kipping, Eliza M.-R. Kempton, Eloy Rodr\\'iguez, Enric Palle, Felipe Murgas, Guillem Anglada-Escud\\'e, Ignasi Ribas, James S. Jenkins, Jose Pe\\~na, Joseph Harrington, Kathleen J. McIntyre, Michael D. Himes, Nicol\\'as T. Kurtovic, Pablo A. Pe\\~na Rojas, Patricio Rojo, Pedro J. Amado, Ricardo Ramirez, R. Paul Butler, Ryan C. Challener, Stefan Dreizler","submitted_at":"2019-05-03T18:29:58Z","abstract_excerpt":"We report Spitzer Space Telescope observations during predicted transits of the exoplanet Proxima Centauri b. As the nearest terrestrial habitable-zone planet we will ever discover, any potential transit of Proxima b would place strong constraints on its radius, bulk density, and atmosphere. Subsequent transmission spectroscopy and secondary-eclipse measurements could then probe the atmospheric chemistry, physical processes, and orbit, including a search for biosignatures. However, our photometric results rule out planetary transits at the 200~ppm level at 4.5$~{\\mu}m$, yielding a 3$\\sigma$ up"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1905.01336","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}