The Frequency of Meteorite Falls throughout the Ages

Abstract

Murray's and Renard's interpretation of the “cosmic spherules” found in deep-sea deposits¹ that they are of cosmic origin, and were probably derived from iron meteors heated to superficial melting during flight through the atmosphere, seems to be generally accepted at present. Having myself studied hundreds of such spherules, extracted from deep-sea cores taken by the Swedish Albatross Expedition (1947–48), I have found Murray's description of their external structure confirmed. In addition, analyses of the composition of individual spherules by the Castaign microanalyser² has confirmed that they contain, besides iron, also nickel and cobalt, which supports their extra-terrestrial origin as well as Murray's hypothesis that they are derived from meteors of the nickel-iron type.