Moss                           ~59º26' N, ~10º42' E

Østfold, Norway

Fell July 14, 2006, ~10:20 hrs local daylight time (UT+2)

Carbonaceous chondrite (CO3.6)

History and physical characteristics: (G. Raade and K. Ødegaard, UOslo; M. Bilet, NorAS) At about 10:20 am on July 14, 2006, a bright fireball traveling SSE-NNW was witnessed by many people and a loud explosion and a rumbling sound was heard in the air above Moss and Rygge in south Norway, on the east side of the Oslofjord. Shortly after, a small meteorite was heard to land on an aluminum sheet and was recovered. Extensive searches in the area have resulted in the recovery of a total of 5 stones (Table 6).  Note that light rainfall occurred in the area on July 29, 30, and 31.

M-S-T: Mass divided between Michael Mazur, Bjørn Sørheim, and Eric Twelker.

Petrography: (J. Grossman, USGS; G. MacPherson, SI; L. Chizmadia, UHaw; A. Rubin, UCLA): Contains abundant small chondrules (most < 200 μm), small (<1 mm) amoeboid olivine aggregates (AOAs) and refractory inclusions, and isolated grains of olivine, troilite, and kamacite set in a gray matrix.  Chondrule types are dominated by type-I PO, with other varieties of type I and II chondrules plus RP, C, and BO all present.  All type I chondrules show diffusional entry of FeO around edges and along cracks of forsterite grains. Olivine histogram is flat, resembling that of Ornans (range Fa_0.3–42, average Fa_19.9, σ=65%, n=60); Cr₂O₃ content of fayalitic olivine is low (0.09±0.09 wt%).  Image analysis gives 2.2 vol% metal and 2.4 vol% FeS.  Refractory inclusions contain spinel, calcic pyroxene, and abundant nepheline that replaces melilite and other primary phases; some perovskite has been transformed to ilmenite. Some AOAs contain relict cores of forsterite, but most of the olivine has been converted to more fayalitic compositions; degree of oxidation of AOAs is similar to type 3.6 CO chondrites such as ALH 77003. Matrix is mildly recrystallized and sulfur-poor; matrix olivine has similar composition to olivine in fine-grained chondrules and inclusions.

Geochemistry: Magnetic susceptibility (R. Bartoschewitz), log χ (10^-9 m^3·kg^-1) = 4.68. Oxygen isotopes (I. Franchi and R. Greenwood, OU), average of two replicates, δ¹⁷O = ‑5.90‰, δ¹⁸O = ‑2.21‰, Δ¹⁷O = ‑4.75‰.

Classification: Carbonaceous chondrite (CO3.6, scheme of Chizmadia et al., 2002); shock stage S2. 

Specimens: Type specimens of 20 g (stone 4) and 2 g (stone 3) are on deposit at SI. Main masses are held by those listed above.