Reply to: Arguments for a comet as cause of the Hopewell airburst are unsubstantiatedOPEN ACCESS 

Kenneth Barnett Tankersley, Stephen D. Meyers, Stephanie A. Meyers & David L. Lentz

Scientific Reports, Volume 12, Article number: 12113 (2022)
Published: 15 July 2022

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The original article was published on 15 July 2022

replying to: R. Neuhäuser and D. L. Neuhäuser; Scientific Reports https://doi.org/10.1038/s41598-022-16211-5 (2022)

“We would like to thank Neuhäuser and Neuhäuser1 for their critical review of our paper2. We presented multi-proxy evidence of an airburst event, which occurred in the Ohio River valley 1699–1567 years ago (252–383 CE). Support for the occurrence of an airburst event includes a disruption in vegetation, meteorites, micrometeorites, and positive anomalies of iridium and platinum in radiocarbon dated, charcoal-rich, Hopewell habitation strata. Our suggestion that the airburst was the result of a comet fragment was based on the overlap of proxies from the Ohio River valley and those recovered from KT boundary, YD boundary, and the Tunguska airburst event sites, which have been attributed to the airburst of comet fragments2,3,4,5.

Neuhäuser and Neuhäuser’s1 commentary raises an important question, What proxies are needed to trace the origin of ancient impactors on the Earth? Ancient airburst events from comet fragments and asteroids are difficult to accurately trace. We recognize that asteroids are the parent bodies of chondrites, and they are physically and chemically distinct from comets. Neuhäuser and Neuhäuser1 provide substantial theoretical evidence that the Hopewell impactor could not have been a comet fragment. Based on their observations, we concede that the Hopewell airburst was more likely the result of an asteroid exploding in the upper atmosphere, an interpretation, which is more in alignment with current interpretations of the KT boundary, YD boundary, and Tunguska events6,7,8.

Comparisons drawn with the Tunguska event emphasize the geographic limitations of first-hand observations. The Tunguska airburst was only observed within an 800 km radius of ground zero9,10,11. This fact is significant and demonstrates that major airburst events are not necessarily observed all over the world in northern latitudes. Eyewitness hand drawings of the Tunguska airburst are nearly identical to the Milford Earthwork (Fig. 1). They depict a red ball that “was twice as large as the sun” with “a fiery broom” that “emitted sparks” behind it12.”

[…]

Neuhäuser and Neuhäuser1 suggest that the Hopewell airburst could have been produced by a small meteorite. However, a meteoritic airburst cannot explain the co-occurrence of both octahedrites and pallasites. Likewise, it does not explain the descendant Native American oral histories and earthwork symbolism. There will always be some degree of ambiguity in explaining the cause of ancient airburst events and tracing the origin of ancient impactors on the Earth. While we agree with Neuhäuser and Neuhäuser’s1 arguments that the Hopewell airburst event was likely the result of an asteroid rather than a comet, their suggestion of a meteoritic airburst is not persuasive.