A 12,800-year-old cosmic impact event may have contributed to the sudden cooling of Earth’s Northern Hemisphere during the Younger Dryas period. Researchers analyzed sediment cores from Baffin Bay near Greenland and found indicators of a comet or asteroid explosion in the ocean floor. The discovery supports the Younger Dryas Impact Hypothesis, which proposes that fragments of a disintegrating comet or asteroid struck Earth, triggering wildfires and plunging the region into a long cold snap.
The study’s findings are significant because they provide new evidence for the hypothesis, which has been debated among scientists since its proposal in 2007. The researchers did not find an impact crater, but instead relied on geochemical evidence found in sediment layers that date back to before the Younger Dryas period began. This lack of definitive evidence led many experts to subscribe to the Meltwater Pulse Hypothesis, which suggests that a deluge of freshwater from melting ice sheets interfered with ocean currents.
However, researchers now suggest that both hypotheses may be true. According to University of South Carolina archaeologist Christopher R. Moore, the Younger Dryas Impact Hypothesis proposes that an impact event would destabilize glacial ice sheets and disrupt ocean conveyor belts. The discovery of metal particles and microspherules in the ocean cores provides evidence for a comet or asteroid impact.
Despite the new findings, skepticism remains among some experts. Applied physicist Mark Boslough expressed doubts about the study’s conclusions, citing more straightforward explanations that are consistent with current scientific understanding. However, the latest analysis adds weight to the Younger Dryas Impact Hypothesis and highlights the ongoing debate over this pivotal event in Earth’s history.
Source: https://gizmodo.com/new-study-fuels-debate-over-world-changing-comet-strike-12800-years-ago-2000644588