London, March 31 : British scientists have deciphered a mysterious ancient clay tablet, which they believe has helped them to solve a riddle over a giant asteroid impact more than 5,000 years ago. According to a report in the Telegraph, the circular clay tablet was discovered 150 years ago by Sir Austen Henry Layard, a leading Victorian archaeologist, in the remains of the royal palace at Nineveh, capital of ancient Assyria, in what is now Iraq.
The tablet shows drawings of constellations and pictogram-based text known as cuneiform.
Researchers have suggested that this tablet may hold clues about a mile-wide asteroid hitting the Earth, forming the shape of the land close to the town of Kofels in the Austrian Alps.
Geologists have long been puzzled over the shape of this particular area, but were unable to prove that an asteroid had caused it.
Now, Alan Bond, the managing director of a space propulsion company, Reaction Engines, and Mark Hempsell, a senior lecturer in astronautics at Bristol University, have cracked the cuneiform code and used a computer programme that can reconstruct the night sky thousands of years ago to provide a new explanation.
According to Bond and Hempsell, their calculations prove that the tablet - a copy made by an Assyrian scribe around 700 BC - is a Sumerian astronomer's notebook recording events in the sky on June 29, 3123 BC.
They said that its symbols include a note of the trajectory of a large object traveling across the constellation of Pisces which, to within one degree, is consistent with an impact at Kofels.
According to Hempsell, the size and route of the asteroid meant that it was likely to have crashed into the Austrian Alps at Kofels. As it traveled 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.
"The ground heating, though very short, would be enough to ignite any flammable material, including human hair and clothes," said Hempsell.
"It is probable more people died under the plume than in the Alps due to the impact blast," he added.