A clay tablet that has baffled scientists for 150 years has been identified as a witness’s account of the asteroid suspected of being behind the destruction of Sodom and Gomorrah.

Researchers who cracked the cuneiform symbols on the Planisphere tablet believe that it recorded an asteroid thought to have been more than half a mile across.

The tablet, found by Henry Layard in the remains of the library in the royal place at Nineveh in the mid-19th century, is thought to be a 700BC copy of notes made by a Sumerian astronomer watching the night sky.

He referred to the asteroid as “white stone bowl approaching” and recorded it as it “vigorously swept along”.

Using computers to recreate the night sky thousands of years ago, scientists have pinpointed his sighting to shortly before dawn on June 29 in the year 3123BC.

About half the symbols on the tablet have survived and half of those refer to the asteroid. The other symbols record the positions of clouds and constellations. In the past 150 years scientists have made five unsuccessful attempts to translate the tablet.

Mark Hempsell, one of the researchers from Bristol University who cracked the tablet’s code, said: “It’s a wonderful piece of observation, an absolutely perfect piece of science.”

He said the size and route of the asteroid meant that it was likely to have crashed into the Austrian Alps at Köfels. As it travelled close to the ground it would have left a trail of destruction from supersonic shock waves and then slammed into the Earth with a cataclysmic impact.

Debris consisting of up to two thirds of the asteroid would have been hurled back along its route and a flash reaching temperatures of 400C (752F) would have been created, killing anyone in its path. About one million sq km (386,000 sq miles) would have been devastated and the impact would have been equivalent to more than 1,000 tonnes of TNT exploding.

Dr Hempsall said that at least 20 ancient myths record devastation of the type and on the scale of the asteroid’s impact, including the Old Testament tale of the destruction of Sodom and Gomorrah and the Ancient Greek myth of how Phaeton, son of Helios, fell into the River Eridanus after losing control of his father’s sun chariot.

The findings of Dr Hempsall and Alan Bond, of Reaction Engines Ltd, are published in a book, A Sumerian Observation of the Köfels’ Impact Event.

The researchers say that the asteroid’s impact would explain why at Köfels there is evidence of an ancient landslide 5km wide and 500m thick.

Tale of devastation

Then the Lord rained on Sodom and Gomorrah brimstone and fire from the Lord out of Heaven; and he overthrew those cities and all the valley, and all the inhabitants of the cities . . . [Abraham] looked down toward Sodom and Gomorrah and toward all the land of the valley, and beheld, and lo, the smoke of the land went up like the smoke of a furnace.

Source: Genesis 19:24-28

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