Researchers have uncovered an ancient meteorite collection dating back two million years - the oldest-ever found on Earth.
The team of scientists, from France's Aix-Marseille Université, made the extraordinary discovery - comprising of 388 separate meteorites - in South America's Atacama Desert.
Using cosmogenic dating, they estimated their average age to be 710,000 years-old.
They also calculated the average rate of falling comet debris over time: 222 meteorites larger than 10g per squared kilometre are said to have fallen every million years.
Thirty per cent of the samples they found were older than one million years, while two samples were older than two million.
All of them were stony meteorites that contained grainy minerals.
The team chose their location because of its colder climate, which helps to preserve the meteors from erosion.
While Antarctica and hot deserts both host a large percentage of meteorites on Earth (about 64 per cent and 30 per cent, respectively), those found in hot deserts or Antarctica are rarely older than half a million years, which limits long-term analysis.
'We found that the meteorite flux seems to have remained constant over this [two-million-year] period in numbers, but not in composition,' he says.
Drouard adds that the team plans to expand their work, measuring more samples and narrowing in on how much time the meteorites spent in space.
'This will tell us about the journey of these meteorites from their parent body to Earth’s surface.'
The study was published in the journal Geology.
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