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Where do our atoms come from?

finmoorhouse.com

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Re: Where do our atoms come from?

#41

Post by schiffern »

layer8 wrote: post #38
schiffern wrote: post #34

Earlier quoted context omitted.

The usual non-technical / non-specialist definition.

I was hoping there is some interesting concept behind your comment. It’s not quite obvious in which sense exactly you would be seeing a human as an explosion.

The word choice of "explosion" is only mildly interesting IMO, and only because it emphasizes that trees and people can be (often more accurately) thought of as events instead of as things.

For me, the more interesting / relevant part (and the reason I brought it up in the first place) is the "interface" aspect.

I, likewise, hope there's "some interesting concept" behind your comments too. I can only presume you'll offer a highly stimulating intellectual payoff for answering your highly tedious questions. :-D

Re: Where do our atoms come from?

#45

Post by dsr_ »

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.

Re: Where do our atoms come from?

#46

Post by flavius29663 »

Laforet wrote: post #25
layer8 wrote: post #22

So if plants are roughly half carbon half water, and the carbon comes from the air while the water comes from the ground, it makes sense that plants spread roughly symmetrically both below the ground and above the ground. Well, a bit more above the ground because they also need photons.

There is a tendency to draw the silhouette of a tree with roots the same size as the canopy but this image is wrong. The root system of most plants run much shallower than people assume because there is no oxygen in deep soil to sustain the roots. A 300 feet giant Sequoia would only reach 12 to 15 feet into the ground.

Sequoia is a special case though. They can afford to be so shallow because the live in families, and all the roots in the forest intertwine and they help each other stay upright. Other forests are not that intertwined. I only knew about that rule (mirror the branches) when it comes to oaks in particular. Other trees have evolved differently: palms will dig for water deep down for example.

Re: Where do our atoms come from?

#47

Post by Aardwolf »

Most interesting parts of this article for me: most of the organisms weight in carbon and other atoms comes from and get recycled into the air, and, most atoms in our body replace every few weeks, we are just "patterns surviving through time".

This seems to be a very big difference with non-organic things, including computers, which even though they are coming pretty close to thinking with LLMs now, keep the same atoms in the same configuration all the time.

Re: Where do our atoms come from?

#49

Post by hotnfresh »

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

I... had never put together that this is probably part of why plants took a (long!) while to colonize land. Between that and there not being a soil-ecology yet, yeah, that paints the picture pretty completely.

Re: Where do our atoms come from?

#50

Post by ww520 »

The elemental atoms ultimately came from the inside of the stars.

Hydrogen was created shortly after the Big Bang when the universe had expanded far enough to cool down that protons and electrons could come together to form hydrogens.

Hydrogens come together later to form the stars. Nuclear fusion inside the stars starts due to the pressure from gravity. Nuclear fusion of hydrogens turns them into heliums.

When the hydrogens at the core of the star are used up, the star collapses and then explodes, throwing the upper crust off.

At the core nuclear fusion of heliums starts, forming lithiums. Nuclear fusion of lithium then forms beryllium. The cycles of nuclear fusion of each element type continue to create the heavier and heavier elements. Carbons are created among the way. So is oxygen.

During each cycle the star explodes and throws off the elements from the upper crust.

After iron is created, nuclear fusion stops. Iron is super stable to resist nuclear fusion. Gravity continues to collapse the star until super nova happens.

Super nova is when all the other heavier elements created. Gold, silver, lead, platinum, uranium and others are created during this explosion.

The elements come together to form the planets and eventually become part of us. So we were created long ago inside a star.

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