The First Recovered Meteorite Fall in Argentina with an Instrumentally Determined Orbit

We report the analysis and meteorite recovery of the Pampean superbolide, a daylight fireball observed over central Argentina on September 13, 2025, at 19:24 UTC (UTC−3 local time). The event was widely recorded by mobile phones and security cameras across southern Buenos Aires Province and La Pampa, and was additionally detected by USG space-based sensors, GLM observations, and five infrasound stations of the CTBTO network. An international collaboration, together with local observers from the Grupo de Astronomía Pampeano, enabled the compilation of eyewitness reports and audiovisual records for trajectory reconstruction, orbital analysis, and strewn-field modelling.

The calibrated atmospheric trajectory derived from three video recordings indicates an observed luminous phase between 65.3 and 15.4 km altitude, with an entry slope of 29° relative to the horizon. Although the beginning of the trajectory was not directly observed, non-calibrated videos indicate a total duration of at least 8 s. Extrapolation of the initial trajectory parameters suggests a lower limit for the beginning height of approximately 91.7 km. The fireball reached a peak brightness of at least −20 mag and released an estimated impact energy of 0.48 kt, based on the information reported by CNEOS. GLM data captured approximately the last 4 s of the event. The light curve exhibits three main brightness peaks, likely associated with fragmentation episodes.

The trajectory reconstruction indicates an atmospheric entry velocity of 19 km/s, while the derived geocentric radiant is located at R.A. = 334.76°, Dec = −9.29°, with a geocentric velocity of 15 km/s. The computed heliocentric orbit (a = 2.35 AU, e = 0.658, i = 0.49°) is consistent with an origin in the inner main asteroid belt. The radiated energy suggests that the object was an asteroid of ~2 m diameter.

A meteorite search campaign conducted in October 2025 between the Lihuel Calel Hills and Cuchillo Có resulted in the recovery of two meteorite fragments of approximately 80 g. Preliminary analyses indicate an ordinary H chondrite composition. Dark-flight modelling using local atmospheric sounding data shows excellent agreement between the recovered meteorites and ejection from the first major fragmentation event at ~28 km altitude with an initial dark-flight velocity of 5 km/s. Dynamical modelling suggests that meteorites in the 4–30 kg range may also have survived atmospheric passage, and new search campaigns are currently being prepared. Pending official Meteoritical Society classification and naming, these samples could represent the first meteorites recovered in Argentina with an instrumentally determined heliocentric orbit.