Multi-sensor Observations of a High-velocity Fireball over the South Atlantic on 2026 April 1

Silber, Elizabeth Allaryce [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000347781409); Rubbrecht, Niels [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)]; Tillier, Clemens E. [Lockheed Martin Corp., Palo Alto, CA (United States). Advanced Technology Center]; Cano, Juan L. [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)]; Landis, Rob R. [National Aeronautics and Space Administration (NASA), Washington, DC (United States); NASA Johnson Space Center, Houston, TX (United States)]; Longenbaugh, Randolph S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)]

doi:10.3847/2515-5172/ae853e

DOE OSTI · 3378004

Multi-sensor Observations of a High-velocity Fireball over the South Atlantic on 2026 April 1

Silber, Elizabeth Allaryce [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000347781409)·Rubbrecht, Niels [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)]·Tillier, Clemens E. [Lockheed Martin Corp., Palo Alto, CA (United States). Advanced Technology Center]·Cano, Juan L. [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)]·Landis, Rob R. [National Aeronautics and Space Administration (NASA), Washington, DC (United States); NASA Johnson Space Center, Houston, TX (United States)]·Longenbaugh, Randolph S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)]

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Abstract

A high-velocity fireball was detected over the South Atlantic (41.9°S, 54.7°W) on 2026 April 1 at 02:13:14 UTC by U.S. Government (USG) sensors, with peak brightness at 90.5 km altitude. The event was well-observed from geostationary orbit by two civilian lightning imagers with near-orthogonal geometry, the Geostationary Operational Environmental Satellite-East Geostationary Lightning Mapper (GLM) and the Exploitation of Meteorological Satellites Meteosat Third Generation Imager 1 Lightning Imager, and it produced low-frequency acoustic signatures. The GLM measured a total radiated energy of 2.4 × 10 10 J, corresponding to a calculated impact energy of 0.086 kt TNT equivalent. Stereoscopic triangulation of the imager tracks yields an independent pre-atmospheric velocity of ~57 km s −1 , some 18% below the USG-reported value. Because orbital provenance is acutely sensitive to the entry velocity, whose reported uncertainty could be substantial, this discrepancy is notable. We document the multi-sensor record and identify the analysis required to assess provenance, which a subsequent study will present.

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Silber, Elizabeth Allaryce [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)] (ORCID:0000000347781409), Rubbrecht, Niels [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)], Tillier, Clemens E. [Lockheed Martin Corp., Palo Alto, CA (United States). Advanced Technology Center], Cano, Juan L. [European Space Operations Centre (ESOC), Darmstadt (Germany). European Space Agency (ESA)], Landis, Rob R. [National Aeronautics and Space Administration (NASA), Washington, DC (United States); NASA Johnson Space Center, Houston, TX (United States)], Longenbaugh, Randolph S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)]. 2026-07-06. Multi-sensor Observations of a High-velocity Fireball over the South Atlantic on 2026 April 1. https://doi.org/10.3847/2515-5172/ae853e

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