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A team in South Africa has discovered the first definitive evidence of a comet strike on Earth some 28 million years ago.
It’s believed to have blown up over what is now Egypt, heating up the Sahara sand to a temperature of up to 2000 degrees Celcius, annihilating everything in its path.
“Comets are unique, comets are extraordinary because they carry very pristine material from our outer solar system and well beyond. So, you literally have a travelling chemical factory, which enters our Earth’s atmosphere and explodes. The comet explodes, it shatters glass, it creates glass – molten glass – there is this lake of fire which creates a blast area of 6,000 square kilometers,” says Professor David Block.
A specimen of the glass is on display in Johannesburg, together with an unusual rock collected in the Sahara 20 years ago. It is filled with microscopic black diamonds, believed to be part of a comet’s nucleus.
The core of a comet is made up of material formed at the same time as our own solar system four and a half billion years ago. Scientists hope this discovery could help unlock some of the secrets of the formation of our solar system.
“NASA and ESA (European Space Agency) generally spend billions of dollars in designing spacecraft which can either send an impactor into the very nucleus of a comet. I think the incredible point about this discovery too is that you don’t need to go into space to collect the material, the material is right here,” said Professor Block.
Until now, scientists had found only grains of cometary material in Earth’s atmosphere and in carbon-rich dust in Antarctic ice.