Apophis is some 350 metres across, considerably larger than the object that is thought to have flattened 2, 000 square kilometres of Siberian forest as it vaporised in the atmosphere above Tunguska in 1908.

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Magazines have traditionally thought of themselves as kind of a locked book, of a complete, discreet object.

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The highlight is the foundation stone of the city of Ai Khanum, laid by Alexander the Great around 300 BC, and thought to be the only object in the world which is known to have been in his hands.

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