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Blood is red due to iron content. Iron can only be produced by nuclear fusion in stars. We are all stardust.
I feel like iron in the blood gets a lot of airtime, but literally all the carbon in our bodies is star stuff too. As is the oxygen making up the water. And almost everything else.
The color of feces is also due (partly) to the iron content of blood. Stars are fecal particles that haven't been shat out yet.
> stardust

What form does stellar iron take once the star it was formed in fails? Is it a gas? Small solids? Individual atoms?

> We are all stardust.

Is that meant to be good? I always chuckle when people make these kind of statements. Is the association to cosmic objects meant to make you feel better about something? I personally don't find stardust particularly interesting. The fundamental forces of nature on the other hand are much more appealing to me.

The claim that elements beyond 94 are only human-made is speculative and probably false. Transuranic elements up to ~100 are believed to be made in, for example, natural fission reactors and extreme stellar conditions. However, it is accurate to say that none of those exist in bulk. They’re more like astatine and francium: so rare that natural occurrence is on the scale of atoms.
The eightfold path, the primordial truth, praise be the ruinous powers!
This article's from 2021. Does anyone know if there are elements (no pun intended) of this classification of element origins that's impacted by those JWST observations of complex early galaxies?
It's a mind boggling that overwhelming majority (more than 98%) of the visible universe's mass are only from the two most lightweight of chemical elements namely Hydrogen and Helium.
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I think the r process and the s process should be listed separately, rather than lumped together.
The thing that is unintuitive to me is the timeline and scale. The age of universe is 13.8B years and age of Earth is 4.5B years. And yet Earth has many of these elements in abundance which are produced by complex chains and in trace quantities. Like the elements need first to be produced in stars, then ejected out, then accumulated into protoplanetary dust, then aggregated into planets. It feels wild to me that the process took only twice as long as what Earth has existed.
With as hot and dense as they are, wouldn’t black hole accretion disks and jets form stuff, too?
Lithium is early in the periodic table (3) and low in abundance. Now that’s a story. There’s even the missing lithium problem.
White dwarf explosions result in zinc? Can someone ELI5 as to how they know this if a white dwarf has never actually been monitored closely? Or are these just theories? Pluto for example was found to have a haze with newer telescopes so what if the observarions from white dwarfs which are so far away based on assumptions - are not correct?