Objects of the same size as the meteorite that hit Ullapool, strike planet once every 100,000 years to one million yearsALAMY

More than a billion years ago a meteorite more than half a mile wide slammed into Earth with the force of 145 billion tonnes of TNT. It hit a barren desert somewhere near the equator, at a spot off the coast of what is now Scotland.

The strike, the largest of its kind discovered in Britain, scattered debris over an area 31 miles across. Over the past 1.2 billion years the portion of the Earth’s crust that bore the brunt has drifted thousands of miles northwards.

Evidence for the meteorite strike was discovered in 2008 near the town of Ullapool, northwest Scotland, by scientists from the University of Oxford and the University of Aberdeen. They noticed deposits of green molten rock fragments sandwiched between sandstones…