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Where do our atoms come from?

finmoorhouse.com

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Re: Where do our atoms come from?

#71

Post by dotancohen »

ww520 wrote: post #70
dotancohen wrote: post #68

Earlier quoted context omitted.

> Iron is super stable to resist nuclear fusion. Why? What property of 26 protons makes it super stable?

It's the electromagnetic force of their 26 electrons that pushes two iron atoms apart such that the gravitational force of the star cannot overcome. Nuclear fusion happens when two atoms come close enough that their strong nuclear force binds them together. Strong nuclear force only has effect in very short distance at the nuclear. Smaller atoms with their smaller size allow gravity of the star to push them together…

Thank you, this is phrased so well!

Re: Where do our atoms come from?

#72

Post by adidum »

wild_pointer wrote: post #3

"The knowledge that the atoms that comprise life on earth - the atoms that make up the human body, are traceable to the crucibles that cooked light elements into heavy elements in their core under extreme temperatures and pressures. These stars- the high mass ones among them- went unstable in their later years- they collapsed and then exploded- scattering their enriched guts across the galaxy- guts made of carbon, ni…

And this can be taken a little further. That we humans are the only part of the universe, as far as we can tell at least, to be aware of all this. We are the part of the universe that allows it to look back at itself. If the universe is a body, we are the eyes of that body. Generally speaking of course. But I find this very empowering as a human being.

Re: Where do our atoms come from?

#74

Post by kenny11 »

This was a fascinating read. One other interesting fact about the carbon in our bodies is that the sort of diet that a person eats over their lifetime can influence the ratio of the different isotopes of carbon in their body due to different plants preferentially using carbon 12 or carbon 13 during photosynthesis. You really are what you eat.

https://naturalhistory.si.edu/sites/default/files/media/file...

Re: Where do our atoms come from?

#75

Post by ww520 »

dotancohen wrote: post #71
ww520 wrote: post #70

Earlier quoted context omitted.

It's the electromagnetic force of their 26 electrons that pushes two iron atoms apart such that the gravitational force of the star cannot overcome. Nuclear fusion happens when two atoms come close enough that their strong nuclear force binds them together. Strong nuclear force only has effect in very short distance at the nuclear. Smaller atoms with their smaller size allow gravity of the star to push them together…

Thank you, this is phrased so well!

Actually I missed one crucial detail. Not just the electrons of the atoms are repelling each other, the positively charged protons of the atoms are repelling each atom as well, even more so. As the protons are tightly packed in the nucleus, it's even more difficult to force the nucleus of two atoms together.

Re: Where do our atoms come from?

#76

Post by yencabulator »

dsr_ wrote: post #45
schiffern wrote: post #23

> In turn, most rain comes from water evaporated from surface water This is true over the whole Earth , but if you look only on land (which is what matters in this case) roughly 80% of rainfall comes from plant transpiration, not evaporation from open bodies of water. https://www.nature.com/articles/nature11983

Trees are self-reproducing solar-powered water pumps.

Taken to a scifi extreme: https://aliens.fandom.com/wiki/Stage_Tree
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