Goodness Gracious - great balls of fire!

Diamonds tell tale of comet that killed off the cavemen.

Fireballs set half the planet ablaze, wiping out the mammoth and America's Stone Age hunters.

A group of US scientists ... will report that they have found a layer of microscopic diamonds at 26 different sites in Europe, Canada and America. These are the remains of a giant carbon-rich comet that crashed in pieces on our planet 12,900 years ago, they say. The huge pressures and heat triggered by the fragments crashing to Earth turned the comet's carbon into diamond dust.

'The shock waves and the heat would have been tremendous,' said West. 'It would have set fire to animals' fur and to the clothing worn by men and women. The searing heat would have also set fire to the grasslands of the northern hemisphere. Great grazing animals like the mammoth that had survived the original blast would later have died in their thousands from starvation. Only animals, including humans, that had a wide range of food would have survived the aftermath.'

The scientists point out that archaeological evidence shows that early Stone Age cultures clearly suffered serious setbacks at this time. In particular, American Stone Age hunters, descendants of the hunter-gatherers who had migrated to the continent from Asia, vanished around this time.

These people were some of the fiercest hunters on Earth, men and women who made magnificent stone spearheads which they used to hunt animals including the mammoth. Their disappearance at this time has been a cause of intense debate, with climate change being put forward as a key explanation. Now there is a new idea: the first Americans were killed by a comet.

I read this and thought how similar it sounded to nuclear fallout and then thought about the possibility of a nuclear Iran. These were not happy thoughts.