Košice: A Fragment Census and the Survival Fraction of a Slovakian Fall

This paper computes a complete entry budget for the Košice fall, working only from published values and stated assumptions. The nominal body has a diameter of 0.9 metres at a bulk density of 3.30e+03 kilograms per cubic metre, giving an incoming mass of 1.26 tonnes. At the published entry speed of 15 kilometres per second its kinetic energy is 0.0339 kilotonnes of TNT equivalent. At the characteristic altitude of 38 kilometres the exponential atmosphere has a density of 6.25e-03 kilograms per cubic metre, the ram pressure on the body is 1.41 megapascals, the stagnation heating flux is 1.06e+04 megawatts per square metre, and the aerodynamic deceleration is 72.4 times terrestrial gravity. The ram pressure first reaches representative material strengths at computed altitudes of 57, 40.5 and 28.9 kilometres for the weakest, intermediate and strongest cases examined. The recovered material, the recovered fragments assembled by search teams, amounts to 11.3 kilograms, which is 0.897 percent of the computed incoming mass. The largest recovered piece, at 2.37 kilograms, has a characteristic diameter of 11 centimetres, a terminal velocity of 92.2 metres per second, a fall time of 195 seconds from the end of the luminous path at 18 kilometres, and a wind drift of 1.95e+03 metres under a representative wind. Over the mapped strewn area of 25 square kilometres, the recovered mass corresponds to 0.452 kilograms per square kilometre. The fragment census gives a mean collected mass of 0.0518 kilograms per fragment. The largest stone, at 2.37 kilograms, carries 21 percent of the recovered total. All values are computed by the deposited program from the stated inputs; scenario calculations accompany every headline figure so that the sensitivity of each conclusion to its inputs is visible in the same record.