The collision happened around 870 000 years ago, a time when Homo erectus, man’s early ancestor, was still roaming the planet. Molten asteroid slabs melted through more than 1.5 kilometres of ice and snow to reach the underlying bedrock... Billions of tons of ice, snow and rock would have been vaporised and thrown into the atmosphere. Rock particles that fell to the ground have been located more that 5 000 kilometres away in Australia. The impact was so immense that it is being considered as the cause of a reversal of the Earth’s magnetic polarity around this time. One...