Tutankhamun’s Brooch Holds Evidence of Ancient Comet Striking Earth
The treasures of the 18th Dynasty pharaoh Tutankhamun were first discovered by Howard Carter and Lord Carnarvon in 1922 when they uncovered his tomb in the Valley of the Kings. Among the gold, jewels and statues was a spectacular brooch, which contains a striking yellow-brown scarab made of a yellow silica glass stone procured from the sand of the Sahara and then shaped and polished by ancient craftsmen.
Scientists discovered that the glass was originally formed 28 million years ago, when an ancient comet entered the earth's atmosphere above Egypt, heating up the sand beneath it to a temperature of about 2,000 degrees Celsius and resulting in the formation of a huge amount of the yellow silica glass, which lies scattered over a 6,000 square kilometre area in the Sahara Desert.
The silica glass was one of the clues that led Professor Jan Kramers of the University of Johannesburg, South Africa, and colleagues to the remarkable discovery. They also analysed a small black diamond-bearing pebble, named ‘Hypatia’, which had been found by an Egyptian geologist in the same area as the silica glass. The pebble represents the very first known hand specimen of a comet nucleus and provides the first definitive proof of a comet striking Earth millions of years ago.
Comet material has never been found on Earth before except as microscopic sized dust particles in the upper atmosphere and in Antarctic ice. Space agencies have spent billions to secure the smallest amounts of pristine comet matter and bringing it back to Earth, now Kramers and her team have a new approach for studying this material without having to go to space to get it.
“Comets contain the very secrets to unlocking the formation of our solar system and this discovery gives us an unprecedented opportunity to study comet material first hand," said Professor David Block of Wits University, a key researcher on the team.
The efforts have grown into an international collaborative research programme involving a growing number of scientists drawn from a variety of disciplines.