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arXiv · 2105.08768

The Chicxulub Impactor: Comet or Asteroid?

Steve Desch·Alan Jackson·Jessica Noviello·Ariel Anbar
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Abstract

A recent paper by Siraj & Loeb (2021) entitled "Breakup of a long-period comet as the origin of the dinosaur extinction" attempts to revive the perennial debate about what type of body hit the Earth 66 million years ago, triggering the end-Cretaceous extinction. Here we critique the paper and assess the evidence it presents. To consider a comet more likely than an asteroid requires extreme assumptions about how comets fragment, conflation of carbonaceous chondrites with specific types of carbonaceous chondrites, and a blind eye to the evidence of the iridium layer.

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Steve Desch, Alan Jackson, Jessica Noviello, Ariel Anbar. 2021-05-18. The Chicxulub Impactor: Comet or Asteroid?. https://doi.org/10.1093/astrogeo/atab069

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