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We present the description of an observation of a fireball recorded during the sunrise on July 15, 2021. Atmospheric trajectory, impact area, and heliocentric orbit were determined on the basis of three instrumental video records. The terminal part of the fireball was not instrumentally recorded due to clouds. Based on our computations, one meteorite was found in the predicted impact area by Polish searchers. The specimen was, soon after recovery, analyzed for the presence of short‐lived radionuclides and the measurement confirms a very fresh fall, coinciding with the time of the fireball event. The recovered meteorite, Antonin, is an unbrecciated L5 chondrite with shock stage S3, weathering grade W0, and bulk density of 3.42 g cm−3. Unusual for L chondrites, it contains assemblages composed of metal and two sulfides, troilite and mackinawite. We interpret these assemblages to have been formed as products of shock metamorphism and post‐shock annealing on the parent body. This suggests that the thermal and collisional history of the Antonin parent body was complex. [ABSTRACT FROM AUTHOR]

On July 15, 2021, a huge fireball was visible over Poland. After the possible strewn field was calculated, the first and so far only sample, with a mass of 350 g, was discovered 18 days after the fireball event. The Antonin meteorite was found August 3, 2021, on the edge of a forest close to a dirt road near Helenow, a small suburb of the city of Mikstat. The rock is an ordinary chondrite breccia and consists of equilibrated and recrystallized lithologies. The boundaries between different fragments are difficult to detect, and the lithologies are of petrologic type 5 and type 4. The rock is moderately shocked (S4) and contains local impact melt areas and thin shock veins. The low‐Ca pyroxene and olivine are equilibrated (Fs20.6 and Fa24.0, respectively), typical of L chondrites. The L chondrite classification is also supported by O isotope data and the results of bulk chemical analysis. The Ti isotope characteristics confirm that Antonin is related to the noncarbonaceous (NC) meteorites. One of the studied thin sections shows an unusual metal–chondrule assemblage, perhaps indicating that the metal in the chondrite is heterogeneously distributed, which is, however, not clearly visible in the element abundances. [ABSTRACT FROM AUTHOR]