Latest news with #BaffinBay
Gizmodo
7 hours ago
- Science
- Gizmodo
New Study Fuels Debate Over World-Changing Comet Strike 12,800 Years Ago
Roughly 12,800 years ago, as Earth was emerging from its last great ice age, temperatures in the Northern Hemisphere suddenly plummeted back to near-glacial conditions. The cause of this abrupt shift—known as the Younger Dryas cool period—remains a mystery to this day, but new evidence may give credence to its most controversial explanation. Researchers analyzed sediment cores extracted from the seafloor of Baffin Bay near Greenland, finding indicators of a cosmic impact event inside the layer that correlates to the Younger Dryas. The findings, published August 6 in the journal PLOS One, suggest that a comet—or its remnants—exploded in Earth's atmosphere at around the same time that this 1,200-year-long cold snap began. The study offers new support for the Younger Dryas Impact Hypothesis. In 2007, researchers proposed that fragments of a disintegrating comet or asteroid struck Earth around 12,800 years ago, triggering wildfires across North America. Such a calamity would have produced enough soot and ash to blot out the Sun and plunge the Northern Hemisphere back into a colder state. It's an elegant explanation, but a highly contested one. Researchers haven't found an impact crater that would prove this event took place, so proponents largely rely on geochemical evidence found in sediment layers that date back to just before the Younger Dryas began. Amid a lack of definitive evidence for the Younger Dryas Impact Hypothesis, most experts instead subscribe to the Meltwater Pulse Hypothesis, which suggests that a deluge of freshwater from the melting ice sheet that covered most of North America during the Pleistocene temporarily interfered with Earth's heat-transporting ocean currents. Previous geochemical evidence from ocean sediment cores supports this idea, but scientists have yet to determine the exact route taken by this apparent flood. The authors of this latest study, led by University of South Carolina archaeologist Christopher R. Moore, suggest that both hypotheses may be true. 'The [Younger Dryas Impact Hypothesis] is often cited as an alternative to the Meltwater Pulse Hypothesis,' Moore said in an interview with PLOS One. 'What many don't understand is that the YDIH proposes the impact event (potentially involving many thousands of impacts and airbursts globally) would destabilize the glacial ice sheet in the Northern Hemisphere, leading to the collapse of massive glacial meltwater lakes and subsequently shutting down the ocean's conveyor belt.' Previous studies of terrestrial sediment cores have found geochemical clues of a comet impact around the onset of the Younger Dryas, but Moore and his colleagues wanted to see whether ocean cores would contain the same clues. If so, this would dispel arguments that land-based evidence of a Younger Dryas impact event resulted from ancient human activities, according to Moore. His team uncovered multiple impact proxies that date back to the appropriate time period inside the ocean cores, including metal particles with compositions that suggest cometary origin and iron- and silica-rich microspherules. Still, not everyone is convinced. 'I do not see anything in this new paper that overcomes the chronic and ongoing problems with their previous papers,' Mark Boslough, an applied physicist and research professor at the University of New Mexico, told Gizmodo in an email. As an outspoken critic of the Younger Dryas Impact Hypothesis, he believes there are much simpler explanations that are more consistent with our current understanding of impact and airburst physics, earth science, and astronomy. 'On the surface, they report materials that sound exotic and impressive, but these are not expected results of extraterrestrial events, and I don't think the authors seriously considered more ordinary explanations,' Boslough said.
Daily Mail
08-08-2025
- Science
- Daily Mail
Groundbreaking find uncovers catastrophic event linked to destruction of legendary Atlantis
A discovery beneath the ocean floor has revealed evidence of a catastrophic event that may be linked to the destruction of the legendary lost city of Atlantis. Some researchers, including well-known author Graham Hancock, have long proposed that around 12,800 years ago, a giant comet passed through Earth's atmosphere, triggering devastation that wiped out advanced civilizations worldwide. While credible proof of Atlantis itself remains elusive, scientists have now uncovered geochemical clues supporting the theory of this cataclysmic event, known as the Younger Dryas. The controversial Younger Dryas Impact Hypothesis (YDIH) suggests Earth passed through debris from a disintegrating comet. The resulting impacts and shockwaves destabilized massive ice sheets, causing massive flooding that disrupted crucial ocean currents and triggered rapid climate cooling. Now, researchers led by the University of South Carolina have uncovered metallic debris, like comet dust and thousands of tiny microspherules, in Baffin Bay seafloor sediments, strengthening the comet impact theory. Archaeologist Marc Young, co-author of the study, told the Daily Mail: 'The Younger Dryas onset is associated with significant changes in human population dynamics all over the planet, though mostly in the northern hemisphere. 'Several independent studies over the last few years have shown conclusively that most of the megafaunal species that went extinct disappeared precisely at that time.' Many mainstream scientists argue that the cooling was caused not by a comet but by glacial meltwater flooding the Atlantic Ocean. This influx of fresh water weakened ocean currents that transport warm tropical waters northward, leading to the temperature drop. However, Young pointed out that 'such cooling events have occurred dozens of times over the last 100,000 years, but none caused megafauna extinctions, wiped out human populations, or deposited a global layer of impact debris like the YD did.' He added: 'Furthermore, the release of meltwater into the oceans at the YD onset was orders of magnitude larger than previous events, causing a near-instantaneous global sea level rise of over 16 feet, while past sea level rises during similar coolings were negligible.' The sediment cores analyzed by the team serve as historical records, preserving layers of mud, sand and particles deposited over millennia. By examining these layers, scientists can reconstruct past climates, ecosystems and geological events. The four cores were collected from locations spanning about 620 miles across Baffin Bay, from shallow waters near Jones Sound to deeper areas near Davis Strait. The cores were taken from water depths between 1,640 and 7,870 feet. Iron-rich and silica-rich tiny spherical particles, or microspherules, were found in layers of the sediment cores dating back 12,800 years. These microspherules formed at very high temperatures, with bubbles, branching surface patterns and aerodynamic shapes that suggested they traveled fast through the air. The iron-rich microspherules also contained small blobs of a low-oxygen metal that is chemically between chromite and chromium-magnetite, minerals found in certain types of meteorites and impact materials. Led by Christopher R Moore, the researchers also detected a pronounced spike in platinum, a rare element often enriched during extraterrestrial impacts, in the same sediment layers containing the microspherules and comet dust. Fragments of melted glass and grains were also found, including melted clusters with iron-rich particles and quartz that melted or boiled at very high temperatures. These also included glass rich in iron, chromium, potassium and titanium. Small blobs of melted chromite, iron-chromium-nickel alloys, iron oxide, and tungsten were found fused onto quartz and magnetite grains from the Younger Dryas Boundary layers in the cores. These metallic blobs mostly consist of native nickel, iron-chromium-nickel alloys, and chromite, and they look very similar to melted splatters on minerals found in South Carolina that have been identified as cometary dust particles. Young emphasized the significance of this ocean-based evidence: 'Until now, no oceanic sediment cores had been used to test the Younger Dryas Impact Hypothesis. 'This is the first and only ocean-based geochemical evidence for the hypothesis since it was proposed in 2007. 'Importantly, it's the first time anyone has looked, and finding this evidence on the very first attempt is very promising. Technically, we have a 100 percent replication rate in ocean cores based on this data.' These findings indicate a geochemical anomaly occurring around when the Younger Dryas event began, but they do not provide direct evidence supporting the impact hypothesis, according to the team. More research is needed to confirm whether the findings are indeed evidence of impact, and to firmly link an impact to climate cooling. 'Our identification of a Younger Dryas impact layer in deep marine sediments underscores the potential of oceanic records to broaden our understanding of this event and its climatological impacts,' Moore said. Co-author Dr Mohammed Baalousha added: 'It is great to implement our unique nano-analytical tools in a new area of study, namely the analysis of nanoparticles generated or transported to the Baffin Bay core site during the Younger Dryas.
