Abu Hureyra, Syria, Part 3: Comet airbursts triggered major climate change 12,800 years ago that initiated the transition to agriculture

Abstract

This study investigates the hypothesis that Earth collided with fragments of a disintegrating comet, triggering Younger Dryas climate change 12,800 years ago. This collision created environmental conditions at Abu Hureyra, Syria, that favored the earliest known continuous cultivation of domestic-type grains and legumes, along with animal management, adding to the pre-existing practice of hunting-and-gathering. The proposed airburst coincided with a significant decline in local populations and led to architectural reorganizations of the village. These events immediately followed the deposition of the Younger Dryas Boundary layer that contains peak concentrations of high-temperature meltglass, nanodiamonds, platinum, and iridium. These proxies provide evidence of a nearby low-altitude airburst by a comet-like fragment of a former Centaur, one of many <300-km-wide bodies in unstable orbits between the giant planets. This large body is proposed to have undergone cascading disintegrations, thus producing the Taurid Complex containing Comet Encke and ~90 asteroids with diameters of ~1.5 to 5 km. Here, we present substantial new quantitative evidence and interpretations supporting the hypothesis that comet fragments triggered near-global shifts in climate ~12,800 years ago, and one airburst destroyed the Abu Hureyra village. This evidence implies a causative link between extraterrestrial airbursts, environmental change, and transformative shifts in human societies.

The Hopewell Cosmic Airburst Event: A review of the empirical evidence

“…Numerous archaeological sites worldwide commonly contain evidence of bonfires, campfires, cremations, structural fires, and, in some cases, entire burned villages. However, for those sites that have been studied for impact-related proxies, all contain one burned layer with a suite of proxies and one or more burned layers without proxies (Ir, Pt, microspherules, and meltglass) [5,11,21,33,34]. In our note that the unmodeled ages overlap the modeled probability distribution (black), confirming the likelihood of synchronicity.…”

“…Based on previous evidence, we conclude that microspherules recovered from the Hopewell strata form at temperatures that greatly exceed those obtained in bonfires, midden fires, campfires, cremations, structural fires, and natural forest fires, as concluded for the Abu Hureyra site and Tall el-Hammam [5,11,33,35]. The extreme temperatures that occur during impact events that form microspherules and meltglass do not occur under natural terrestrial conditions except for lightning strikes [5,11,33,34]. However, lightning produces fulgurites, which were not observed in any Hopewell stratum and are easily distinguished from impact meltglass [5,11,33,34].…”

“…Searching for potential airburst/impact proxies Previous investigations of near-surface cosmic airbursts and impacts have used a suite of microscopic impact-related proxies, including micrometeorites, meltglass, microspherules, and positive anomalies of platinum group elements such as iridium (Ir) and platinum (Pt) [5,11,[24][25][26][27][28][29][30][31][32][33][34][35][36]. Consequently, we examined Hopewell sediments from 11 archaeological sites in the Ohio River valley for evidence of these impact-related proxies (Figures 1-16).…”

“…The Hopewell proxy-rich occupation layers from the Ohio River valley appear comparable to the Abu Hureyra site in Syria and the Tall el-Hammam site in Jordan [5,33,34]. For the impact proxies at Abu Hureyra, Moore et al [33] performed furnace experiments demonstrating that bulk sediment can melt at ~1200°C.…”

“…and impacts can form vesicular, scoria-like meltglass [5,24,33,34] that results from the high temperatures and thermo-mechanical shock produced during a cosmic impact event. Meltglass has been found at ground zero at the Trinity nuclear explosion site in New Mexico [40], the Australasian strewnfield in southern China and Australia [40], and Meteor Crater in Arizona [41,42].…”