Ancient humans may have witnessed catastrophic fireballs from a 62-mile-wide comet near the end of the last Ice Age that spurred blazes larger than the 'dinosaur killers'
- Study suggests fragments of a 62-mile-wide comet struck 12,800 years ago
- This would have caused massive fires across roughly 10 percent of Earth's land
- The resulting dust, blocking out sunlight, would have brought on a near Ice Age
- Large species died out, humans saw greater risk of cancer, and ozone depleted
Nearly 13,000 years ago, Earth may have plunged suddenly into an apocalyptic scene; a barrage of fireballs lit up the sky, followed by powerful shock waves and fires that blazed across 10 percent of the planet’s land surface.
The sky turned black as dust blocked out the sunlight, and temperatures rapidly plummeted, causing plants to die out and glaciers to advance, in what soon became a near ice age state.
And, humans were there to witness it all – with grave consequences.
This is according to new research, which suggests fragments of a 62-mile-wide disintegrating comet struck Earth 12,800 years ago and spurred burning events larger than those caused by the ‘dinosaur killers.’
According to a new study, Earth was plunged suddenly into an apocalyptic scene 12,800 years ago; a sudden barrage of fireballs lit the sky, followed by powerful shock waves and fires that blazed across 10 percent of the planet’s land surface. An artist's impression is pictured
The new study on geochemical and isotopic markers, which involved two dozen researchers, argues that a cosmic impact thousands of years ago left behind high concentrations of platinum across the Northern Hemisphere.
This could be found at a number of sites, including ice cores collected from the Greenland Ice Sheet, linked to the Younger Dryas boundary – a period roughly 12,800 years ago toward the end of the last Ice Age when glacial conditions temporarily began to advance again.
According to the new research, an impact could have triggered this cooling episode.
‘The work includes measurements made at more than 170 different sites around the world,’ said Adrian Melott, University of Kansas Emeritus Professor of Physics & Astronomy.
‘The hypothesis is that a large comet fragmented and the chunks impacted the Earth, causing this disaster.
‘A number of different chemical signatures – carbon dioxide, nitrate, ammonia, and others – all seem to indicate that an astonishing 10 percent of the Earth’s land surface, or about 10 million square kilometers, was consumer by fires.’
New research suggests fragments of a 62-mile-wide disintegrating comet struck Earth 12,800 years ago and spurred burning events larger than those caused by the ‘dinosaur killers.’ Artist's impression
The pollen analysis indicated that pine forests were likely burned off and later replaced by poplar.
This species is known to colonize cleared areas.
The impact would have been equally catastrophic for the humans and animals alive at the time.
WHEN WERE EARTH'S FIVE GREAT EXTINCTION EVENTS?
Five times, a vast majority of the world's life has been snuffed out in what have been called mass extinctions.
The first of the traditional big five extinction events, around 540 million years ago, was probably the second most severe. Virtually all life was in the sea at the time and around 85% of these species vanished.
Late Devonian mass extinction
About 375-359 million years ago, major environmental changes caused a drawn-out extinction event that wiped out major fish groups and stopped new coral reefs forming for 100 million years.
Five times, a vast majority of the world's life has been snuffed out in what have been called mass extinctions. The most famous may be the End-Cretaceous, which wiped out the dinosaurs. Artist's impression
The largest extinction event and the one that affected the Earth's ecology most profoundly took place 252 million years ago. As much as 97% of species that leave a fossil record disappeared forever.
Dinosaurs first appeared in the Early Triassic, but large amphibians and mammal-like reptiles were the dominant land animals. The rapid mass extinction that occurred 201 million years ago changed that.
End-Cretaceous mass extinction
An asteroid slammed down on Earth 66 million years ago, and is often blamed for ending the reign of the dinosaurs. Some larger species of the late Pleistocene became extinct as a result, and the human population experienced cultural shifts and decline due to the many health problems that would have followed the event.
‘Computations suggest that the impact would have depleted the ozone layer, causing increases in skin cancer and other negative health effects,’ Melott said.
‘The impact hypothesis is still a hypothesis, but this study provides a massive amount of evidence, which we argue can only be all explained by a major cosmic impact.’
According to the researchers, the remnants of the ancient disintegrating comet likely still remain in our solar system today.
Car-sized asteroid is spotted just HOURS before narrowly skimming past Earth's satellites at 24,000 miles from the planet's surface
- The 2018 BD asteroid is 8.2 to 18 feet (2.5 to 5.5 metres) wide
- This is third time an asteroid has flown past under one lunar distance this year
- Its next close approach will be on 19th November 2018
- It won't be coming as close as yesterday's approach for another 115 years
A newly-discovered asteroid hurtled past our planet at a distance of just 24,168 miles (38 895km) yesterday - just seven hours after it was discovered.
The car-sized 2018 BD asteroid is 8.2 to 18 feet (2.5 to 5.5 metres) wide and passed so close to our planet it was nearly at the altitude at which satellites orbit.
Anything that flies closer than six million miles of our planet is a near earth asteroid and could cause severe damage were it ever to crash into Earth.
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A newly discovered asteroid hurtled past our planet at a distance of just 24,168 miles (38 895km) yesterday - just seven hours after it was discovered (stock image)
The asteroid was discovered at 08:24 UTC (08:24 GMT, 03:24 ET) on 18th January by Catalina Sky Survey and flew by at 15:43 UTC (15:43 GMT, 10:45 ET) that day.
This is the third time an asteroid has flown past our Earth within one lunar distance since the start of this year,
Its next close approach will be on 20:37 UTC (20:37 GMT, 15:37 ET) on 19th November 2018 - but it won't be coming as close as it was yesterday for another 115 years at least.
The news comes just days after it was revealed asteroid 2019 BC, which is larger than the Burj Khalifa, is due to fly past our planet in less than two weeks.
The 2018 BD asteroid is 8.2 to 18 feet (2.5 to 5.5 metres) wide and passed so close to our planet it was nearly at the altitude at which satellites orbit
This makes it nearly 15 times faster than the world's quickest manned aircraft - the hypersonic North American X-15, which travelled at 4,520mph (7,300kmh).
The asteroid is around 0.7 miles (1.1km) wide - making it longer than the Burj Khalifa in Dubai, which stands at 0.5 miles high (0.8km).
It is set to pass by our planet on the 4th February at a distance of around 2,615,128 miles (4,208,641km) away - which is relatively close in space terms.
The asteroid was discovered at 08:24 UTC on 18th January. This is the third time an asteroid has flown past our Earth within one lunar distance since the start of this year
Nasa describes asteroids as 'hazardous' if they come within 4,600,000 miles (7,403,00km) of our planet.
Currently Nasa would not be able to deflect an asteroid if it were heading for Earth but it could mitigate the impact and take measures that would protect lives and property.
This would include evacuating the impact area and moving key infrastructure.
Finding out about the orbit trajectory, size, shape, mass, composition and rotational dynamics would help experts determine the severity of a potential impact.
However, the key to mitigating damage is to find any potential threat as early as possible.
'As of December 24, there are 17,495 known Near-Earth Objects (NEOs) around our planet; 17,389 are asteroids', a Nasa spokesperson told the Express last month.
'This year, we discovered 1,985 new near Earth asteroids. There were 1888 such objects discovered in 2016 and 1,571 in 2015'.
The news comes just days after it was revealed asteroid 2019 BC, which is larger than the Burj Khalifa, is due to fly past our planet in less than two weeks. The asteroid is around 0.7 miles (1.1km) wide - making it longer than the Burj Khalifa in Dubai (pictured)
Nasa is currently moving forward with a refrigerator-sized spacecraft capable of preventing asteroids from colliding with Earth. A test with a small, nonthreatening asteroid is planned for 2024.
This is the first-ever mission to demonstrate an asteroid deflection technique for planetary defence.
The Double Asteroid Redirection Test (DART) would use what is known as a kinetic impactor technique—striking the asteroid to shift its orbit.
The impact would change the speed of a threatening asteroid by a small fraction of its total velocity, but by doing so well before the predicted impact, this small nudge will add up over time to a big shift of the asteroid's path away from Earth.
In February 2013 a 19-metre meter (62-feet) meteor exploded in the skies above Chelyabinsk in Russia.
The energy - which was equivalent to 500,000 tonnes of TNT - and injured more than 1,000 people.
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