An asteroid breakup 160 Myr ago as the probable source of the K/T impactor

  title={An asteroid breakup 160 Myr ago as the probable source of the K/T impactor},
  author={William F. Bottke and David Vokrouhlicky and David Nesvorn{\'y}},
The terrestrial and lunar cratering rate is often assumed to have been nearly constant over the past 3 Gyr. Different lines of evidence, however, suggest that the impact flux from kilometre-sized bodies increased by at least a factor of two over the long-term average during the past ∼100 Myr. Here we argue that this apparent surge was triggered by the catastrophic disruption of the parent body of the asteroid Baptistina, which we infer was a ∼170-km-diameter body (carbonaceous-chondrite-like… Expand
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