{"paper":{"title":"Simulated LSST Observations of Real Metre-scale Imminent Impactors","license":"http://creativecommons.org/licenses/by/4.0/","headline":"LSST simulations with real fireballs predict eight imminent impactors discovered four days before impact over a 10-year survey.","cross_cats":["astro-ph.IM"],"primary_cat":"astro-ph.EP","authors_text":"Hadrien A. R. Devillepoix, Michael A. Frazer, Sophie E. Deam","submitted_at":"2026-02-06T02:19:47Z","abstract_excerpt":"As of mid-2026, 11 objects have been discovered prior to impacting the Earth, with warning times between 2 - 20 hours. Using real metre-sized Earth impactors from the last decade, we ask the question: ``If the Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) had been operating over the last decade, how many imminent impactors would it have observed and discovered pre-impact, and how early would these discoveries have been?'' We use the LSST Solar System Survey Simulator Sorcha and a population of real fireballs observed by orbital sensors over the last decade to investigate w"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"We predict that the LSST will discover 8 +/- 2 imminent impactors over its nominal 10 year survey, at the low end of previous estimations. However, we predict these objects to be discovered 4 days pre-impact, substantially earlier than the current average.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"That the sample of 216 real fireballs from the last decade is representative of the metre-scale impactor population LSST will encounter, and that the modified linking algorithm will perform as modeled for fast-moving objects without significant false positives or misses.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Simulations of real past impactors predict LSST will discover 8 +/- 2 imminent impactors over 10 years at 4 days pre-impact on average, lower rate but earlier than prior estimates.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"LSST simulations with real fireballs predict eight imminent impactors discovered four days before impact over a 10-year survey.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"485c5e81b5da3f2ac29277426e1cbcad9a36efa1c6e75ac66d52132b26b24c61"},"source":{"id":"2602.06314","kind":"arxiv","version":2},"verdict":{"id":"009e03d7-6acc-43c3-b010-d8cf6db8deeb","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-16T07:01:20.965817Z","strongest_claim":"We predict that the LSST will discover 8 +/- 2 imminent impactors over its nominal 10 year survey, at the low end of previous estimations. However, we predict these objects to be discovered 4 days pre-impact, substantially earlier than the current average.","one_line_summary":"Simulations of real past impactors predict LSST will discover 8 +/- 2 imminent impactors over 10 years at 4 days pre-impact on average, lower rate but earlier than prior estimates.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"That the sample of 216 real fireballs from the last decade is representative of the metre-scale impactor population LSST will encounter, and that the modified linking algorithm will perform as modeled for fast-moving objects without significant false positives or misses.","pith_extraction_headline":"LSST simulations with real fireballs predict eight imminent impactors discovered four days before impact over a 10-year survey."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2602.06314/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}