Earth's heavy metals result of supernova explosion

Earth's heavy metals result of supernova explosion
Artist’s impression of a collapsar . Credit: NASA Goddard Space Flight Centre

That gold on your ring finger is stellar—and not just in a complimentary way.

In a finding that may overthrow our understanding of where Earth's heavy elements such as gold and platinum come from, new research by a University of Guelph physicist suggests that most of them were spewed from a largely overlooked kind of star explosion far away in space and time from our planet.

Some 80 per cent of the heavy elements in the universe likely formed in collapsars, a rare but heavy element-rich form of supernova explosion from the gravitational collapse of old, typically 30 times as weighty as our sun, said physics professor Daniel Siegel.

That finding overturns the widely held belief that these elements mostly come from collisions between or between a neutron star and a black hole, said Siegel.

His paper co-authored with Columbia University colleagues appears today in the journal Nature.

Using supercomputers, the trio simulated the dynamics of collapsars, or old stars whose gravity causes them to implode and form .

Under their model, massive, rapidly spinning collapsars eject heavy elements whose amounts and distribution are "astonishingly similar to what we observe in our solar system," said Siegel. He joined U of G this month and is also appointed to the Perimeter Institute for Theoretical Physics, in Waterloo, Ont.

Most of the elements found in nature were created in in stars and ultimately expelled in huge stellar explosions.

Heavy elements found on Earth and elsewhere in the universe from long-ago explosions range from gold and platinum, to uranium and plutonium used in nuclear reactors, to more exotic chemical elements such as neodymium found in consumer items such as electronics.

Until now, scientists thought that these elements were cooked up mostly in stellar smashups involving neutron stars or black holes, as in a collision of two observed by Earth-bound detectors that made headlines in 2017.

Ironically, said Siegel, his team began working to understand the physics of that merger before their simulations pointed toward collapsars as a heavy element birth chamber. "Our research on neutron star mergers has led us to believe that the birth of black holes in a very different type of stellar explosion might produce even more gold than neutron star mergers."

What collapsars lack in frequency, they make up for in generation of heavy elements, said Siegel. Collapsars also produce intense flashes of gamma rays.

"Eighty per cent of these heavy elements we see should come from collapsars. Collapsars are fairly rare in occurrences of supernovae, even more rare than neutron star mergers—but the amount of material that they eject into space is much higher than that from neutron star mergers."

The team now hopes to see its theoretical model validated by observations. Siegel said infrared instruments such as those on the James Webb Space Telescope, set for launch in 2021, should be able to detect telltale radiation pointing to heavy elements from a collapsar in a far-.

"That would be a clear signature," he said, adding that astronomers might also detect evidence of collapsars by looking at amounts and distribution of heavy element s in other stars across our Milky Way galaxy.

Siegel said this research may yield clues about how our galaxy began.

"Trying to nail down where heavy elements come from may help us understand how the galaxy was chemically assembled and how the galaxy formed. This may actually help solve some big questions in cosmology as are a nice tracer."

This year marks the 150th anniversary of Dmitri Mendeleev's creation of the periodic table of the chemical elements. Since then, scientists have added many more elements to the periodic table, a staple of science textbooks and classrooms worldwide.

Referring to the Russian chemist, Siegel said, "We know many more elements that he didn't. What's fascinating and surprising is that, after 150 years of studying the fundamental building blocks of nature, we still don't quite understand how the universe creates a big fraction of the elements in the periodic table."


Explore further

Researchers suggest collapsar accretion disks might be source of heaviest elements

More information: Daniel M. Siegel et al, Collapsars as a major source of r-process elements, Nature (2019). DOI: 10.1038/s41586-019-1136-0
Journal information: Nature

Citation: Earth's heavy metals result of supernova explosion (2019, June 13) retrieved 18 July 2019 from https://phys.org/news/2019-06-earth-heavy-metals-result-supernova.html
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Jun 13, 2019
A clever reader reads evidence and does not bother with lies.

"-Sun Photospheric composition (by mass)
Hydrogen…………..73.46%
Helium……………….24.85%
Oxygen………………..0.77%
Carbon ………………..0.29%
Iron……………………..0.16%
Neon…………………..0.12%
All nebulae observed in the Milky Way Galaxy ...
in general in that approximately 90 percent of the constituentatoms are hydrogen and nearly all the rest are helium, with oxygen, carbon, neon, nitrogen, and the other elements together making up about two atoms per thousand."

Jun 13, 2019
-Earth Chemical composition
Silica……………SiO2……….60.2%
Alumina………...Al2O3….....15.2%
Lime…………….CaO………...5.5%
Magnesia……….MgO…….....3.1%
iron(II) oxide……FeO…….....3.8%
sodium oxide…..Na2O…......3.0%
potassium oxide.K2O……....2.8%
iron(III) oxide…...Fe2O3…....2.5%
water…………….H2O……….1.4%
carbon dioxide….CO2……...1.2%
titanium dioxide…TiO2….....0.7%

-The Moon Chemical composition
………………………………….…Maria…….Highland
Silica…………..……SiO2…….45.4%......45.5%
Alumina…………...Al2O3…...14.9%.......24.0%
Lime………………...CaO…….11.8%.......15.9%
iron(II) oxide……..FeO….......14.1%.........5.9%
magnesia…………..MgO…......9.2%..........7.5%
titanium dioxide..TiO2….........3.9%..........0.6%
sodium oxide…....Na2O…......0.6%...........0.6%
Total…………………………….99.9%.........100.0%


Jun 13, 2019
I wish the article would have pointed out that it isn't the percentage of gold in the solar system thats is representative of collapstars, but rather the ratios of the heavy elements themselves. For a given neutron source driving a fast r-process synthesis, different sorts of systems produce different ratios of golds to platinum, to uranium, etc. If one takes a look at very similar chemical elements with different atomic weights, for example platinum, iridium, ruthenium, etc. the production of each element depends heavily on the number of neutrons available. But the absolute number of heavy element atoms varies according to source chemistry. Looking at the ratio's then allows the elimination of source chemistry and zeros in on the particular r-process system.

In other words, the research here is quite valid and sustainable, but they didn't explain it well enough for uneducated and ignorant readers like wduckass

Jun 14, 2019
Hmmmm. I'll look for data to support this; if the authors are right, then we'll find them. They've already apparently found one: the europium-to-iron ratio. At least they don't claim the heavy elements are *all* created in their simulation; only 80%.

Jun 14, 2019
It is not easy to be so blind (about knowledge not need nor speak).

Heavy Elements of Sun:
Oxygen.............0.77 %
Carbon.............0.29 %
Iron...................0.16 %
Neon.................0.12 %
Nitrogen............0.09 %
Silicon...............0.07 %
Magnesium.......0.05 %
Sulfur................0.04 %
.....................................Ukupno..........................1,59 %

Earth, heavy elements.................................. = 99.4%.

Heavy elements in supernova remnants:......... traces.

Keyword blind here is a more appropriate word of word a complete ignoramus.

Jun 14, 2019
@wduckss:
you claim that because the photosphere (the outer 100km) of our star (with no known past novas or supernovas) doesn't contain heavy metals, all the research presented here is wrong? Cool story. That is some great critical thinking on your part. /s

Jun 14, 2019
A smart reader checks:
which is the point of boiling heavy elements (when they become gas) and compares it to the Sun's (stars) temperature.

I do not seek faith and believers. I'm asking you to use your head and database.

Before the story, think and check. Do not slam without any connection and proof.

Jun 15, 2019
I recommend you take your own advice. And some lessons in astrophysics. Hint: a boiling point is not absolute, it depends on factors like surrounding pressure.

Jun 15, 2019
"At 19% of the solar radius, near the edge of the core, temperatures are about 10 million kelvins and fusion power density is 6.9 W/m 3 , which is about 2.5% of the maximum value at the solar center."

Maybe this helps you in thinking about the points of boiling of heavy elements and pressure forces inside in the stars.

Jun 16, 2019
A smart reader................


.........would actually be writing these papers, and performing these simulations, instead of posting complete drivel on here.

Jun 16, 2019
All of this has been published in scientific journals, forums (unexplained-mysteries.com, newtheory.ru, Теоретическая астрономия astronomy.net.ua) , academia.edu .. and my site https://www.svemi...rti.com/ .

I'm posting comments (all less often) here and Dailygalaxy.

Do you mean to say that only people who do not know the substance are commenting here?

They ( "smart" scientists that I comment) write for money.
Astrophysics is my hobby (I'm all financing).

Jun 17, 2019
No, you're into conspiracy theories, pseudo-science and pretending to be smart by posting utter nonsense with big words that sound impressive to people who don't know what they mean.

Jun 17, 2019
Do you know or talk without a connection?

If you know convincing judges and publishers in scientific journals; that you. consider. that they are stupid. and they have no idea!

Second: What a conspiracy, if I enclose official evidence that can be checked?

Of course a "smart" reader, who do not see away from his the nose (sorry, of the article), he can not see, that the evidence which he disputes, also reviewed and published and to be found in the official database.

Conspiracy is: use the official evidence against concoction! ?
Bravooo!

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