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Impact cratering is a ubiquitous geological process oil the terrestrial planets. Meteorite impact craters are the most visible product of impact events, but there is a growing recognition that large aerial bursts or airbursts should occur relatively frequently throughout geological time. In this contribution, we report on an Unusual impact glass-the Dakhleh Glass (DG)-which is distributed over an area of similar to 400 km(2) of the Dakhleh Oasis, Egypt. This region preserves a rich history of habitation stretching back to over 400,000 years before the emergence of Homo sapiens. We report oil observations made during recent fieldwork and subsequent analytical analyses that strengthen previous Suggestions that the DG formed during all impact event. The wide distribution and large size of DG specimens (Lip to similar to 50 cm across), the chemistry (e.g., CaO and Al(2)O(3) contents up to similar to 25 and similar to 18 wt%, respectively), the presence of lechatelierite and burnt sediments, and the inclusion of clasts and spherules in the DG is inconsistent with known terrestrial processes of glass formation. The age and other textural characteristics rule out a human origin. Instead, we draw upon recent numerical modeling of airbursts to suggest that the properties of DG, Coupled with the absence of a confirmed crater, can best be explained by melting of surficial sediments as a result of a large airburst event. We Suggest that glass produced by such events should, therefore, be more common in the rock record than impact craters, assuming that the glass formed in a suitable preserving environment.