KNYAHINYA

Following detonations, a shower of stones numbering more than 1000, and weighing ~500 kg, fell at 5:00 P.M. in the Ukraine, USSR. A strewn field with dimensions of 2 x 0.75 miles was delineated. The nearly spherical mass of Knyahinya had an estimated preatmospheric diameter of 90 cm, corresponding to a mass of ~1,300–1,400 kg, before it was broken into two nearly symmetrical sections upon impact; the largest section weighed 293 kg. The CRE age of Knyahinya as inferred from cosmic-ray track data and cosmogenic Ne ratios is 38 m.y. Knyahinya has proven to be instrumental in studies of cosmogenic nuclide production systematics due to its simple single-stage exposure history and its simple shielding geometry, allowing exact depth profiles to be determined.

Although Knyahinya has an official classification of L5 based on its trace element composition, it is partially resolved into an intermediate L/LL chondrite group based on studies involving the Co abundance in matrix kamacite and on its bulk metallic iron content similar to that of an LL chondrite. Contrarily, the Ir/Au atomic ratio of Knyahinya falls within the H range (3.4–3.8) rather than the LL–L range (2.6–3.5). Further information regarding the establishment of the L/LL meteorites as a unique chondrite suite from a unique parent body can be found on the Inman page.

Members of the L/LL chondrite group include the L/LL3 Esperance, the L/LL4 Seemore Downs, Bjurböle, and Cynthiana, the L/LL5/6 Sahara 97021, and the L/LL6 Acfer 041, as well as the partially resolved L/LL3 Inman and L/LL6 Holbrook and Sultanpur. The classification of Knyahinya remains to be further resolved through future studies. The specimen of Knyahinya shown above is a 1.93 g partial slice. The photo below shows a print depicting the Knyahinya fireball—from a book published in Denmark a few years after the fall (click image for title page).

Photo courtesy of Lars Pedersen