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The periodic table, colour coded by the likely origin of each element

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Re: The periodic table, colour coded by the likely origin of each element

#51

Post by dredmorbius »

hermitcrab wrote: post #20
dandare wrote: post #4

How did elements created by a merging neutron stars and dying low-mass stars get down to our planet?

The follow up question is, how come the different elements aren't uniformly mixed within the earth. Or perhaps formed into stratified layers with the densest at the centre? E.g. Why are there 'deposits' of gold relatively close to the surface? Something to do with interaction of the physical and chemical properties of the elements with local variations in conditions?

The Earth is mostly stratified: light rocky silicate crust, heavier (though also rocky) magnesium-silicate mantle, core of mostly nickle-iron and heavier elements, which formed during the iron catastrophe.

Crustal deposits of heavier minerals largely result from late bombardment (after the crust had formed, about 100 million years after Earth's formation itself), geothermal and tectonic activity (volcanism, rift zones, vents), and biological mobilisation and concentration (e.g., lighter elements in coal and limestone, but notably, banded iron formations). Events such as the hypothesized Tethys collision could of course also have influenced distribution.

Gold forms veins typically in quartzes through differential precipitation AFAIU.

Ore formation is its own fascinating subfield of geology, and is underappreciated by many advocates of space mining.

https://en.wikipedia.org/wiki/Abundance_of_elements_in_Earth...

https://en.wikipedia.org/wiki/Planetary_differentiation

https://en.wikipedia.org/wiki/Iron_catastrophe

https://en.wikipedia.org/wiki/Ore_genesis

Re: The periodic table, colour coded by the likely origin of each element

#52

Post by dredmorbius »

Diederich wrote: post #48
ncmncm wrote: post #38

Earlier quoted context omitted.

Some did, some didn't. All the iridium, platinum, gold we find landed.

> All the iridium, platinum, gold we find landed Cool. Do you have a quick reference for the 'landed' part? As opposed to being part of the planet from the beginning. Thanks!

https://www.livescience.com/15938-earth-precious-metals-spac...

https://www.oakton.edu/user/4/billtong/eas100/cosmicorigins....

Re: The periodic table, colour coded by the likely origin of each element

#53

Post by saagarjha »

identity0 wrote: post #46
jacknews wrote: post #3

The image shown by wikipedia https://en.wikipedia.org/wiki/Chemical_element seems more complete and better laid out, and is also by cmglee ( https://commons.wikimedia.org/wiki/User:Cmglee ), based on data from Jennifer Johnson at Ohio State University ( http://www.astronomy.ohio-state.edu/~jaj/nucleo/ ): https://upload.wikimedia.org/wikipedia/commons/3/31/Nucleosy...

Brown: made by monkeys on terrestrial planets

Also made in the similar ways as their surrounding elements, but generally don't stick around for long enough for anyone to really care.

Re: The periodic table, colour coded by the likely origin of each element

#54

Post by saagarjha »

Tepix wrote: post #39
AllegedAlec wrote: post #12

Earlier quoted context omitted.

Our sun is about 4.6B year old. There were a few other generations of stars that lived and died before our sun came about, and these spewed out the heavier elements that make up our solar system.

It must have been a somewhat dull first generation of stars and planets with only Hydrogen and Helium around. On the other hand, giant stars explode after just a few million years so it didn't take long for other elements to appear.

I think they make up for their dullness by being absolutely massive–hundreds of solar masses, if not more.

Re: The periodic table, colour coded by the likely origin of each element

#55

Post by saagarjha »

hermitcrab wrote: post #45
hermitcrab wrote: post #44

Earlier quoted context omitted.

Memory is a bit rusty on this (30 years since I did nuclear physics) but elements have stable and unstable isotopes (with the same number of protons and a different number of neutrons). E.g. Carbon 12 and 13 are stable and Carbon 14 is unstable (half-life 5730 years). An atom will keep decaying until it reaches a stable form. Then it will stay like that until some nuclear fusion or fission event occurs.

Consequently most chains of decay will reach a stable form long before they get to Hydrogen.

For heavy elements this usually means a terminal at the 206, 207, or 208 isotopes of lead or thallium-205; radioactive isotopes smaller than that usually quickly hit a "nearby" stable isotope.

Re: The periodic table, colour coded by the likely origin of each element

#56

Post by rini17 »

WorldMaker wrote: post #33
arethuza wrote: post #10

For some completely irrational reason I was slightly disappointed that the gold in my wedding ring was only from a neutron star merger and probably not from a supernova. However, reading the relevant wikipedia page I came across this part: "this single neutron star merger event generated between 3 and 13 Earth masses of gold" https://en.wikipedia.org/wiki/Gold#Gold_production_in_the_Un... Can't wait to refer to that…

Neutron Star Mergers & Acquisitions sounds like a great title for book or TV show.

I have a very-soon-merging neutron star pair to sell to you.

Re: The periodic table, colour coded by the likely origin of each element

#57

Post by ninkendo »

Tuna-Fish wrote: post #17
dandare wrote: post #4

How did elements created by a merging neutron stars and dying low-mass stars get down to our planet?

Two neutron stars merging is an extremely energetic event which emits vast amounts of degenerate neutron star material at speeds above escape velocity. Pretty much instantly after this material is liberated from the pressure and gravity of the neutron star, it starts decaying into normal matter, producing a vast menagerie of (generally very neutron-rich) elements, which then follow their decay chains until they end u…

I've always wondered, does the presence of heavy elements on earth (ones which are likely to have formed via neutron star mergers) indicate that a pair of neutron stars merged relatively nearby our sun when it formed? Or is there just a diffuse amount of these elements in typical protostellar clouds all over the galaxy?

Perhaps a simpler way of asking: are the heavy elements we find on earth typical for an average planet? Or does a planetary system have to be "lucky" enough to have formed near a neutron star merger, for it to have elements like gold in measurable quantities?

Re: The periodic table, colour coded by the likely origin of each element

#58

Post by WorldMaker »

rini17 wrote: post #56
WorldMaker wrote: post #33

Earlier quoted context omitted.

Neutron Star Mergers & Acquisitions sounds like a great title for book or TV show.

I have a very-soon-merging neutron star pair to sell to you.

"You want to be on the ground floor of this IPO because I'm telling you it's going to just be exploding gold (and other elements)."

Re: The periodic table, colour coded by the likely origin of each element

#59

Post by wiml »

identity0 wrote: post #46
jacknews wrote: post #3

The image shown by wikipedia https://en.wikipedia.org/wiki/Chemical_element seems more complete and better laid out, and is also by cmglee ( https://commons.wikimedia.org/wiki/User:Cmglee ), based on data from Jennifer Johnson at Ohio State University ( http://www.astronomy.ohio-state.edu/~jaj/nucleo/ ): https://upload.wikimedia.org/wikipedia/commons/3/31/Nucleosy...

Brown: made by monkeys on terrestrial planets

Or made naturally on terrestrial planets (Radon's colored brown).
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