Refuting the sensational claim of a Hopewell-ending cosmic airburstOPEN ACCESS 

Kevin C. Nolan, Andrew Weiland, Bradley T. Lepper, Jennifer Aultman, Laura R. Murphy, Bret J. Ruby, Kevin Schwarz, Matthew Davidson, DeeAnne Wymer, Timothy D. Everhart, Anthony M. Krus & Timothy J. McCoy

Scientific Reports, Volume 13, Article number: 12910


“arising from: K. B. Tankersley et al.; Scientific Reports (2022).

Tankersley et al.1 claim a cosmic airburst over modern-day Cincinnati, Ohio in the 3rd or fourth century CE catalyzed the decline of Hopewell culture. This claim is extraordinary in the face of hundreds of archaeological investigations in the Middle Ohio River Valley (MORV) that have heretofore provided no evidence of a widespread cataclysm or “social decline” in need of explanation. Tankersley et al. misrepresent primary sources, conflate discrete archaeological contexts, improperly use chronological analyses, insufficiently describe methods, and inaccurately characterize the source of supposed extraterrestrial materials to support an incorrect conclusion. While charcoal and burned soils are found on virtually all excavated Middle Woodland archaeological sites in the region, these have prosaic explanations. Many of the burned “habitation surfaces” mentioned are actually prepared surfaces for ceremonial fires, not the result of a synchronous regional catastrophe. Radiocarbon dated samples from one context are mistakenly attributed to distinct and unrelated contexts. The chronological analysis does not support the notion of a single event spanning 15,000 km2. The composition of their supposed extraterrestrial materials is inconsistent with an origin in comet or asteroid events. In sum, there is no evidence to support the conclusion that a comet exploded over modern-day Cincinnati in the third or fourth century CE.

Attempts to associate extraterrestrial events as the direct cause of various ancient cultural declines, i.e. “cosmic catastrophism,” have appeared in several recent papers2,3. These catastrophist narratives have met consistent challenge on evidentiary, methodological, and theoretical grounds4,5. These scenarios oversimplify complex and dynamic human–environment interactions and are steeped in pseudoscientific beliefs rather than anthropological theories of social decline that can be tested using the archaeological record. Tankersley et al.’s proposition that a comet or meteor airburst caused the decline of the Hopewell culture is the latest example of a cosmic claim dooming a culture with no substantive archaeological or geologic evidence. Instead, the Hopewell archaeological record demonstrates continued habitation with gradual sociopolitical and economic reorganization (e.g., a cessation in large ceremonial earthwork construction) and changes in settlement patterns within the MORV6,7,8,9,10,11.

Tankersley and colleagues’ argument depends on several misinterpretations and mischaracterizations of the Hopewell archaeological record to arrive at their conclusion. There are no catastrophically burned, fire-hardened, charcoal-rich habitation surfaces documented at any Hopewell site. The soil profiles published in the body of the article (Figs. 2–12 in 1) and the soil descriptions in their supplemental material (Tables S5, S7, S10, S13, S16, S18, S21, S23, S25, S28, and S30) do not show evidence of in situ burning as claimed. The burned surfaces referenced in the article are in fact ceremonial basins, localized burned areas, or burned floors within mounds12,13. In aggregate, these burned areas do not support widespread regional burning by a catastrophic event, but a series of intentionally burned surfaces as a regionally-distributed socioreligious practice.