The mysterious Hypatia stone may hold the earliest evidence of a Type Ia . supernova

In 1996, an archaeologist named Ali A. Barakat was doing field work in the Egyptian desert and found an unusual shiny black pebble now known as the Hypatia Stone (after Hypatia of Alexandria). Studies conducted over the past several years indicate that the stone is from extraterrestrials. According to last paper Published in the journal Icarus, the body of the father of the stone was likely born in the aftermath of a rare Type I supernova explosion.

The Hypatia stone was found in an area southwest of Egypt known as the Libyan Desert Glass, which resulted from an extreme surface heating event, and is very likely a meteorite. The Hypatia stone may also have come from this collision, although recent evidence suggests that the comet may have been a main body.

Jan Kramers of the University of Johannesburg and several colleagues have investigated the Hypatia stone for many years. Kramers compared the internal structure of the Hypatia stone to a fruitcake: a poorly mixed paste that makes up the bulk of the pebble (mixed matrices), with the mineral grains inherent in the stone inclusions representing cherries and nuts. He likened the secondary materials in the cracks of the stone to the flour that sprinkled the cracks in the fruitcake.

In 2013, Kramers and colleagues published results chemical analysis Which provided strong evidence in favor of the stone being part of the comet. This analysis was a startling proposition because most comet fragments found on Earth are microscopic dust particles in the upper atmosphere or buried in Antarctic ice. The comet hypothesis explains the presence of microscopic diamonds in the stone, which likely formed in the impact when the comet erupted over Egypt about 28.5 million years ago. (Perhaps the presence of these tiny diamonds is the reason the stone was able to reach the ground without disintegrating)

However, work by other research teams in 2015 ruled out the presence of a comet or meteorite as the source of the stone, based on analyzes of the noble gases and nuclear probe. The mineral matrix does not resemble the composition of known meteorites: for example, it contains a huge amount of carbon and a small amount of silicon. So if it didn’t come from Earth, which isn’t typical of a comet or meteorite fragment, where did it come from?

Kramers and others 2018 Micro Metal Analysis revealed that the matrix also contains a high concentration of polyaromatic hydrocarbons (PAH) – a major component of interstellar dust – and those microscopic diamonds. The grains consist of aluminum, silver iodine, phosphide, silicon carbide, as well as a nickel-phosphorous compound, with very little iron. The latter are elements that usually make up the bulk of rocky planets. Based on this, Kramers and his colleagues suggested that the Hypatia stone contained material that was present in space before our solar system formed.