Illinois, Cook Co.
Date of fall/find:
Fell 2003, March 26 2350
Total known weight:
18 kg (approx.)
Number of pieces:
many pieces (shower)
Ordinary chondrite (L5), brecciated, shock veins
Shock stage: S5
Meteoritical Bulletin record: Click here
A bright fireball was seen by numerous observers in parts of Illinois, Indiana, Wisconsin and Ohio around midnight of March 26, 2003; numerous stones fell, mostly concentrated in the area of the village of Park Forest; at least two houses in Park Forest were struck, as was the Fire Station; dozens of other stones or fragments of stones were recovered in the area in the hours and days following the fall; total
mass recovered is more than 18 kg, largest stone ~3 kg in possession of finder; description and classification (S.Simon, Univ. Chicago; M.Wadhwa, Field Mus. Chicago; P.Sipiera, Planet. Sci. Found.): most stones are partly to fully fusion-crusted; some broken faces show brecciated texture, angular clasts; cross-cutting dark veins and dark pockets may be of impact melt origin; no visible chondrules in hand sample; abundant troilite and metal visible in some broken faces; chondrules and maskelynite are visible in thin section; mean olivine composition Fa24.7, mean low-Ca pyroxene Fs20.7Wo1.6; shock stage S5, S.S.Russell et al., Met. Bull. 87, MAPS, 2003, 38, No. 7 (Suppl.), p.A189. Fall and find circumstances, classification, short-lived cosmogenic radionuclides, and oxygen isotopic composition, S.B.Simon et al., MAPS, 2003, 38, No. 7 (Suppl.), p.A139 (abs.); see also, MAPS, 2004, 39, p.625. Orbit, meteoroid's energy, trajectory, and velocity derived from satellite data and ground-based measurements and observations, P.Brown et al., MAPS, 2004, 39, p.1781.