14 DAY TRIAL // Researchers in South Africa and their colleagues claim to have found evidence that, 28 million years ago, a comet entered out planet's atmosphere and exploded over present-day Egypt.
They say that, when this event took place, the sand in the Sahara Desert heated to about 2,000 degrees Celsius (3,632 degrees Fahrenheit).
Furthermore, they argue that the bits and pieces of yellow silica glass that are still scattered over some 6,000 square kilometers in this part of the world formed in the aftermath of this impact.
In a paper set to be published in the journal Earth and Planetary Science Letters, the researchers explain that they reached the conclusion that our planet was struck by a comet millions of years ago after analyzing the makeup of an odd-looking black pebble.
The pebble was discovered by an Egyptian geologist some time ago in an area where several pieces of yellow silica glass had been found over the years.
Investigations have revealed that, rather than having formed on our planet or being a meteor remain, this pebble used to be part and parcel of a comet's nucleus.
“Comets always visit our skies – they’re these dirty snowballs of ice mixed with dust – but never before in history has material from a comet ever been found on Earth,” says Professor David Block of Wits University.
“It’s a typical scientific euphoria when you eliminate all other options and come to the realization of what it must be,” Professor Jan Kramers of the University of Johannesburg adds.
“NASA and ESA [the European Space Agency] spend billions of dollars collecting a few micrograms of comet material and bringing it back to Earth, and now we’ve got a radical new approach of studying this material, without spending billions of dollars collecting it,” Professor Kramers further explains.
The pebble said to prove that, millions of years ago, our planet was hit by a comet was named Hypatia, after Hypatia of Alexandria, i.e. the first well-known woman mathematician, astronomer and philosopher.