The Chicxulub Impactor: Comet or Asteroid?

Steve Desch, Alan Jackson, Jessica Noviello, Ariel Anbar

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.

Comments: To be published in Astronomy and Geophysics

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Cite as: arXiv:2105.08768 [astro-ph.EP] (or arXiv:2105.08768v1 [astro-ph.EP] for this version)

Submission history

From: Steve Desch 

[v1] Tue, 18 May 2021 18:34:53 UTC (498 KB)

https://arxiv.org/abs/2105.08768

Astrobiology