Newswise – New forensic chemistry indicates that the stone named Hypatia from the Egyptian desert may be the first hard evidence found on Earth of a Type Ia supernova explosion. These rare supernovae are among the most energetic events in the universe.
That’s the conclusion of 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 discovered a series of highly unusual chemical clues in a small fragment of the Hypatia Stone.
In the new research, they weed out “cosmic suspects” for the stone’s origin in a painstaking process. They pieced together a timeline going back to the earliest stages of the formation of Earth, our Sun, and the other planets in our solar system.
A cosmic timeline
Their hypothesis about the origin of Hypatia begins with a star: a red giant star collapsed into a white dwarf star. The collapse would have occurred inside a gigantic dust cloud, also called a nebula.
This white dwarf ended up in a binary system with a second star. The white dwarf star ends up “eating” the other star. At some point, the “hungry” white dwarf exploded into a Type Ia supernova inside the dust cloud.
After cooling, the remaining gas atoms from supernova Ia began to stick to particles in the dust cloud.
“In a sense, we could say that we ‘caught’ an Ia supernova explosion ‘in the act’, as the gas atoms from the explosion were captured in the surrounding dust cloud, which eventually formed the body. relative of Hypatia,” says Kramers.
A huge “bubble” of this mixture of dust atoms and supernova gas never interacted with other dust clouds.
Millions of years would pass, and eventually the “bubble” would slowly become solid, like a “cosmic dust bunny.” Hypatia’s “parent body” would become solid rock at some point in the early stages of our solar system’s formation.
This process probably happened in a cold, uneventful outer part of our solar system – in the Oort Cloud or the Kuiper Belt.
At some point, Hypatia’s bedrock began to rush towards Earth. The heat from entering the Earth’s atmosphere, combined with the pressure from the impact in the Great Sea of Sand southwest of Egypt, created micro-diamonds and shattered bedrock.
The Hypatia Stone picked up in the desert must be one of many fragments from the original impactor.
“If this hypothesis is correct, the Hypatia Stone would be the first hard evidence on Earth of a Type Ia supernova explosion. Perhaps just as importantly, it shows that an individual anomalous ‘packet’ of dust from outer space could actually be incorporated into the solar nebula from which our solar system was formed, without being completely mixed together. says Kramers.
“This flies in the face of the conventional view that the dust from which our solar system was formed was thoroughly mixed.”
Three million volts for a small sample
To piece together the timeline of Hypatia’s formation, researchers used several techniques to analyze the strange stone.
In 2013, a study of argon isotopes showed that the rock did not form on earth. He must have been an alien. A 2015 study of the noble gases in the fragment indicated that it could not have come from any known type of meteorite or comet.
In 2018, the UJ team published various analyses, including the discovery of a mineral, nickel phosphide, which was not previously found in any object in our solar system.
At this point, Hypatia was proving difficult to analyze further. The trace metals Kramers and Belyanin were looking for couldn’t really be “seen in detail” with the equipment they had. They needed a more powerful instrument that wouldn’t destroy the tiny sample.
Kramers began analyzing a dataset that Belyanin had created a few years earlier.
In 2015, Belyanin carried out a series of proton beam analyzes at iThemba Laboratories in Somerset West. At the time, Dr. Wojciech Przybylowicz was spinning the three million volt machine.
In search of a model
“Rather than exploring all the incredible anomalies that Hypatia has, we wanted to explore if there is an underlying unity. We wanted to see if there was some sort of coherent chemical pattern in the stone,” says Kramers.
Belyanin carefully selected 17 targets from the small sample for analysis. All were chosen to be well removed from the earth minerals that had formed in the cracks of the original rock after its impact in the desert.
“We identified 15 different elements in Hypatia with much greater precision and accuracy with the proton microprobe. This gave us the chemical ‘ingredients’ we needed, so that Jan could start the next process of analyzing all the data,” says Belyanin.
The proton beam also excludes the solar system
The first big new clue from the proton beam analyzes was the surprisingly low level of silicon in the stone targets of Hypatia. Silicon, along with chromium and manganese, were less than 1% to be expected for anything formed in our inner solar system.
In addition, high iron, sulfur, phosphorus, copper and vanadium content was evident and abnormal, Kramers adds.
“We found a consistent pattern of trace mineral abundance that is completely unlike anything in the solar system, primitive or evolved. Asteroid belt objects and meteors also don’t fit this. Then we looked outside the solar system,” says Kramers.
Not from our neighborhood
Next, Kramers compared the concentration pattern of the element Hypatia with what one would expect to see in the dust between stars in our Milky Way galaxy’s solar arm.
“We looked to see if the pattern we get from the middle interstellar dust in our arm of the Milky Way galaxy matches what we see in Hypatia. Again, there was no similarity,” adds Kramers.
At this point, the proton beam data had also ruled out four “suspects” of where Hypatia might have formed.
Hypatia did not form on earth, was not part of any known type of comet or meteorite, did not form from the average dust of the inner solar system, or from the average interstellar dust no more.
Not a red giant
The next simplest possible explanation for the pattern of element concentration in Hypatia would be a red giant star. Red giant stars are common in the universe.
But the proton beam data also ruled out a mass outflow from a red giant star: Hypatia had too much iron, too little silicon, and too low concentrations of heavy elements heavier than iron.
Nor a type II supernova
The next “suspect” to consider was a Type II supernova. Type II supernovae cook a lot of iron. It is also a relatively common type of supernova.
Again, the proton beam data for Hypatia ruled out a promising suspect with “forensic chemistry.” A type II supernova was highly unlikely as a source of strange minerals like nickel phosphide in the pebble. There was also too much iron in Hypatia compared to silicon and calcium.
It was time to take a close look at the predicted chemistry of one of the most spectacular explosions in the universe.
heavy metal factory
A rarer type of supernova also makes a lot of iron. Type Ia supernovae only occur once or twice per galaxy per century. But they make most of the iron (Fe) in the universe. Most of the steel on earth was once the element iron created by supernova Ia.
Furthermore, established science indicates that some Ia supernovae leave behind very distinctive “forensic chemistry” clues. This is due to the way some Ia supernovae are configured.
First, a red giant star at the end of its life collapses into a very dense white dwarf. White dwarf stars are generally incredibly stable for very long periods of time and very unlikely to explode. However, there are exceptions to this.
A white dwarf star could begin to “pull” material from another star in a binary system. We can say that the white dwarf star “eats” its companion star. Eventually, the white dwarf becomes so heavy, hot and unstable that it explodes into a supernova Ia.
Nuclear fusion in the explosion of supernova Ia is expected to create highly unusual patterns of element concentration, predict accepted scientific theoretical models.
Moreover, the white dwarf star that explodes in a supernova Ia is not only reduced to crumbs, but literally reduced to atoms. Matter from supernova Ia is sent into space in the form of gas atoms.
In an extensive literature search of star data and model results, the team could not identify a similar or better chemical fit for the Hypatia stone than a specific set of supernova Ia models.
Evidence of forensic elements
“All Supernova Ia data and theoretical models show much higher proportions of iron to silicon and calcium than Supernova II models,” says Kramers.
“In this regard, the data from the Proton Beam Laboratory on Hypatia matches the data and models of supernova Ia.”
In total, eight of the 15 elements analyzed are within the expected proportion ranges with respect to iron. These are the elements silicon, sulfur, calcium, titanium, vanadium, chromium, manganese, iron and nickel.
However, the 15 elements analyzed in Hypatia do not all correspond to the predictions. In six of the 15 elements, the proportions were between 10 and 100 times higher than the ranges predicted by theoretical models for type 1A supernovae. These are the elements aluminum, phosphorus, chlorine, potassium, copper and zinc.
“Since a white dwarf star is formed from a dying red giant, Hypatia could have inherited these element proportions for the six elements of a red giant star. This phenomenon has been observed in white dwarf stars in other research,” adds Kramers.
If this hypothesis is correct, the Hypatia Stone would be the first tangible evidence on Earth of a Type Ia supernova explosion, one of the most energetic events in the universe.
The Hypatia Stone would be a clue to a cosmic story that began during the early formation of our solar system, and would end up many years later in a distant desert strewn with other pebbles.
