Extraterrestrial stone could be the first evidence on Earth of a supernova explosion Ia

A 3 gram (0.1 ounce) sample of a Hypatia stone. The researchers found a consistent pattern of 15 elements in the Hypatia stone. This pattern is very different from anything in our solar system or our solar neighbourhood, in the Milky Way. Credit: Romano Serra

New chemical “forensics” suggest that a stone called Hypatia from the Egyptian desert could be the first physical evidence found on Earth of a Type Ia supernova explosion. Rare supernovae are among the most energetic events in the universe.

That’s the conclusion of a new research study by Jan Kramer, George Pelianin, and Hartmut Winkler from[{” attribute=””>University of Johannesburg, and others that has been published in the journal Icarus.

Since 2013, Belyanin and Kramers have discovered a series of highly unusual chemistry clues in a small fragment of the Hypatia Stone.

In the new research, they meticulously 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.

The tiny samples of the extraterrestrial Hypatia stone next to a small coin. Rare type Ia supernovas are some of the most energetic events in the universe. Researchers found a consistent pattern of 15 elements in the Hypatia stone. The pattern is completely unlike anything in our solar system or our solar neighborhood, the Milky Way. Prof Jan Kramers (University of Johannesburg) is the lead author. Credit: Jan Kramers

“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 sometime 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 the earth’s atmosphere, combined with the pressure of impact in the Great Sand Sea in southwestern 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.

The Hypatia stone could be the first concrete evidence on Earth of a Type Ia supernova explosion. Type Ia supernovae are rare — and some of the most energetic events in the universe. UJ researchers have found a consistent pattern of 15 elements in the Hypatia stone discovered in Egypt. This pattern is very different from anything in our solar system or our solar neighborhood in[{” attribute=””>Milky Way. But most of the elements match the pattern of supernova type Ia models. Prof Jan Kramers (University of Johannesburg) is the lead author. Credit: Therese van Wyk

“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.

A high-voltage proton beam shows three trace elements in the extraterrestrial Hypatia stone, and their concentrations. Here, we see sulphur, iron and nickel for targets 1 and 2 within region 14 on the sample. Dr Georgy Belyanin (University of Johannesburg) used a 3-million Volt proton beam to analyse the tiny fragment of the stone. Credit: Georgy Belyanin

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.

At that stage 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 would not destroy the tiny sample.

Kramers started analyzing a dataset that Belyanin had created a few years before.

In 2015, Belyanin had done a series of analyses on a proton beam at the iThemba Labs in Somerset West. At the time, Dr. Wojciech Przybylowicz kept the three-million Volt machine humming along.

In search of a pattern

“Rather than exploring all the incredible anomalies Hypatia presents, we wanted to explore if there is an underlying unity. We wanted to see if there is some kind of consistent chemical pattern in the stone,” says Kramers.

Belyanin carefully selected 17 targets on the tiny sample for analysis. All were chosen to be well away from the earthly 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 Jan could start the next process of analyzing all the data,” says Belyanin.

UJ researchers find that most of the elements they analysed in the extraterrestrial Hypatia stone fit the predictions from supernova Ia models well. The high-voltage proton beam data shows that for 9 of the 15 elements, concentrations are close to the predicted values. Prof Jan Kramers (University of Johannesburg) is the lead author. Credit: Jan Kramers

Proton beam also rules out solar system

The first big new clue from the proton beam analyses was the surprisingly low level of silicon in the Hypatia stone targets. The silicon, along with chromium and manganese, were less than 1% to be expected for something formed within our inner solar system.

Further, high iron, high sulfur, high phosphorus, high copper, and high vanadium were conspicuous and anomalous, adds Kramers.

“We found a consistent pattern of trace element abundances that is completely different from anything in the solar system, primitive or evolved. Objects in the asteroid belt and meteors don’t match this either. So next we looked outside the solar system,” says Kramers.

Various analyzes of the Hypatia stone in Egypt indicate that it did not form on Earth or within our solar system. A new study shows that it may have preserved an unusual chemical pattern similar to that of the Supernova Ia explosion. Dr. Georgi Pelyanin (University of Johannesburg) used a 3 million volt proton beam to analyze a small part of the stone. Credit: Therese Van Wyck

not from our time

Kramers then compared the concentration pattern of Hypatia to what one would expect to see in interstellar dust in our solar arm of the Milky Way.

“We looked to see if the pattern we get from the average interstellar dust in our arm of the Milky Way fit what we see in Hypatia. Again, there was absolutely no similarity,” Kramers adds.

At this point, the proton beam data also ruled out four “suspects” of where Hypatia might be.

Hypatia did not form on Earth, was not part of any known type of comet or meteorite, and was not made up of average dust of the inner Solar System, and not of average interstellar dust either.

Not a red giant

The next simplest possible explanation for Hypatia’s element concentration pattern would be a red giant star. Red giant stars are common in the universe.

But the proton beam data ruled out the mass flux from a red giant star, too: Hypatia had too much iron, too little silicon, and very low concentrations of heavy elements heavier than iron.

There is no type 2 supernova

The next “suspect” to consider was a type II supernova. Type II supernovas cook a lot of iron. They are also a relatively common type of supernova.

Once again, Hypatia’s proton beam data ruled out the most promising “forensic chemical” suspect. It is highly unlikely that a Type II supernova is a source of exotic minerals such as nickel phosphide in the pebble. There was also a lot more iron in Hypatia compared to silicon and calcium.

It’s time to examine the predicted chemistry of one of the universe’s most dramatic explosions.

heavy metal factory

A rarer type of supernova also produces a lot of iron. Type Ia supernovae only occur once or twice per galaxy every century. But they make the most iron (Fe) in the universe. Most of the steel on Earth was once the element iron, which was created by Ia supernovae.

Also, established science says that some Ia supernovae leave behind very distinct clues about “forensic chemistry”. This is because of the way some Ia supernovae are prepared.

First, at the end of its life, a red giant star collapses into a very dense white dwarf star. White dwarf stars are usually incredibly stable for very long periods and are very unlikely to explode. However, there are exceptions to this.

A white dwarf star can begin to “pull” matter from another star in a binary system. One could say that the white dwarf star “devours” its companion star. Eventually, the white dwarf becomes so heavy, hot, and unstable that it explodes into a supernova Ia.

Nuclear fusion during a supernova Ia explosion should create highly unusual patterns of element concentration, as predicted by accepted scientific theoretical models.

Also, the white dwarf star that explodes in supernova Ia not only breaks into tiny bits, but literally explodes into atoms. Supernova Ia material is delivered into space in the form of gas atoms.

In a comprehensive search of star data and model results, the team was unable to identify any chemical similar or best-suited to the Hypatia stone from a specific set of supernova Ia models.

Elements of forensic evidence

“All supernova Ia data and theoretical models show much higher proportions of iron than silicon and calcium than supernova 2 models,” Kramers says.

“In this respect, the data from the Hypatia Proton Beam Laboratory are consistent with the data and models of the Ia supernova.”

Altogether, eight of the 15 items analyzed correspond to the expected ranges of ratios for iron. These are the elements silicon, sulfur, calcium, titanium, vanadium, chromium, manganese, iron and nickel.

However, not all of the fifteen items analyzed in Hypatia meet expectations. In six of the 15 elements, the ratios were 10 to 100 times higher than the ranges predicted by theoretical models for Type 1A supernovae. These are the elements aluminum, phosphorous, chlorine, potassium, copper and zinc.

“Because a white dwarf star consists of a dying red giant, Hypatia inherited these proportions of elements for the six elements from a red giant star. This phenomenon has been observed in white dwarf stars in other research,” Kramers adds.

If this hypothesis is correct, then the Hypatia stone would be the first concrete evidence on Earth of a Type Ia supernova explosion, one of the most energetic events in the universe.

The Hypatia stone will be evidence of a cosmic story that began during the early formation of our solar system, and was found many years later in a remote desert strewn with other pebbles.

Reference: “The Chemistry of Extraterrestrial Carboniferous Stone” Hypatia: A Perspective on Dust Heterogeneity in Interstellar Space” by Jan D. Kramers, Georgy A. Icarus.
DOI: 10.1016 / j.icarus.2022.115043