New chemistry “forensics” indicate that the stone named Hypatia from the Egyptian desert could be the first tangible evidence found on Earth of a supernova type Ia explosion. These rare supernovas are some of the most energetic events in the universe.
This is the conclusion from a new study published in the journal Icarus, by Jan Kramers, Georgy Belyanin and Hartmut Winkler of the University of Johannesburg, and others.
Since 2013, Belyanin and Kramers have been uncovering a series of highly unusual chemistry clues in a small fragment of the Hypatia Stone. In their new research, they eliminate “cosmic suspects” for the origin of the stone in a painstaking process. They have pieced together a timeline stretching back to the early stages of the formation of Earth, our sun and the other planets in our solar system.
A cosmic timeline
Their hypothesis about Hypatia’s origin starts with a star: A red giant star collapsed into a white dwarf star. The collapse would have happened inside a gigantic dust cloud, also called a nebula.
That white dwarf found itself in a binary system with a second star. The white dwarf star eventually “ate” the other star. At some point the “hungry” white dwarf exploded as a supernova type Ia inside the dust cloud.
After cooling, the gas atoms which remained of the supernova Ia started sticking to the particles of the dust cloud.
“In a sense we could say, we have ‘caught’ a supernova Ia explosion ‘in the act,’ because the gas atoms from the explosion were caught in the surrounding dust cloud, which eventually formed Hypatia’s parent body,” says Kramers.
A huge “bubble” of this supernova dust-and-gas-atoms mix never interacted with other dust clouds.
Millions of years would pass, and eventually the “bubble” would slowly become solid, in a “cosmic dust bunny” kind of way. Hypatia’s “parent body” would become a solid rock some time in the early stages of formation of our solar system.
This process probably happened in a cold, uneventful outer part of our solar system—in the Oort cloud or in the Kuiper belt.
At some point, Hypatia’s parent rock started hurtling towards Earth. The heat of entry into earth’s atmosphere, combined with the pressure of impact in the Great Sand Sea in south-western Egypt, created micro-diamonds and shattered the parent rock.
The Hypatia stone picked up in the desert must be one of many fragments of the original impactor.
“If this hypothesis is correct, the Hypatia stone would be the first tangible evidence on Earth of a supernova type Ia explosion. Perhaps equally important, it shows that an individual anomalous ‘parcel’ of dust from outer space could actually be incorporated in the solar nebula that our solar system was formed from, without being fully mixed in,” says Kramers.
“This goes against the conventional view that dust which our solar system was formed from, was thoroughly mixed.”
Three million volts for a tiny sample
To piece together the timeline of how Hypatia may have formed, the researchers used several techniques to analyze the strange stone.
In 2013, a study of the argon isotopes showed the rock was not formed on earth. It had to be extraterrestrial. A 2015 study of noble gases in the fragment indicated that it may not be from any known type of meteorite or comet.
In 2018 the UJ team published various analyses, which included the discovery of a mineral, nickel phosphide, not previously found in any object in our solar system.