 The researchers argue that the material, which dates back nearly 13,000 years, was formed at temperatures of as the result of a bolide impact.They argue that these findings support the controversial Younger Dryas Boundary (YDB) hypothesis that the bolide impact occurred at the onset of the Younger Dryas.The hypothesis has been questioned in research that concluded that most of the results cannot be confirmed by other scientists and that the authors misinterpreted the data.