In 1996, scientists discovered what may be the strangest stone ever found, in an equally strange section of the Sahara desert that’s littered with unique yellow glass. Nicknamed the Hypatia stone, the relic was later found to be extraterrestrial in origin, but was unlike any known kind of meteorite or comet. A new study has deepened the mystery even further, finding that Hypatia could predate the formation of the Solar System, or have interstellar origins.
A few years ago, a University of Johannesburg team declared the Hypatia stone to be the first “comet nucleus” – the rocky, solid center of a comet – found on Earth. The idea supports the accepted story behind the Libyan Desert Glass Field where it was discovered, since the explosion from the impact would have flash-fried the sand and created the yellow silica glass dotting the area.
But the Hypatia stone’s origin story isn’t quite that simple. The Johannesburg team has now analyzed its mineral composition and found that although it’s definitely a space rock, it doesn’t follow the basic recipe common to everything else in the Solar System.
Billions of years ago, the Solar System began life as a huge cloud of dust and gas surrounding the Sun. Over time, this material clumped together to form the planets and dwarf planets, with the leftover fragments drifting around as asteroids and comets. As such, these wayward travelers are generally made of the same stuff as Earth. But that’s not the case with Hypatia.