So helium is a limited resource. Okay gotcha. So why not take two hydrogen atoms. Take their protons and neutrons. And just fucking start squeezing them together until you get helium?
And I don’t mean in the same way you get H2. Those are still separate from each other.
This can be done, it’s called nuclear fusion and the sun does it constantly. The practical limitation is, largely, overcoming the electrostatic force.
Basically, because the atoms are similarly charged, squeezing them together is like trying to push together the North sides of two magnets: they repel each other. It takes a massive amount of energy to squeeze them together hard enough to overcome that repulsion, fortunately the sun has enough energy to do this fairly easily. It is much more difficult for humans to do.
… I feel like you just perfectly eli5 nuclear fusion. I’m using this example next time it comes up.
I can tell you know this, I’m just tacking it on for those who don’t:
Why do the nuclei stick together at all, once you’ve pushed them together? Because the nuclear force, which is attractive instead of repulsive, is just a little bit stronger. OK, so why then doesn’t the nuclear force just pull all atoms together? Because it is short range, and only works once the nuclei are “touching.”
I know that much, but actually how can a force be stronger but short range?
So does the sun just have huge amounts of helium? Where is it getting all that helium? Can we have some
It’s making it, from the tons of hydrogen it has in the fusion process. The energy and the reason stars even do this is because all of that mass that close together spontaneously does that; starts fusing.
We can’t have any, because a star will use up all the hydrogen to make helium, then start using all of the helium to make carbon and oxygen. Then start to make…
This is overly simplified and it varies from star to star (the more massive the star, the longer it churns through “making” elements into more “complex” elements) until its core is all iron, at which point fusion becomes a net negative.
From there other things can happen like novae. All throughout this life process though, that “elemental conversion” is happening faster on the outside as opposed to the core, and stellar winds do blow off heavier elements that enrich the interstellar medium.
We need a shovel that can plunge into the sun’s core if we want its helium, TL;DR.
Our sun will stop at carbon, then hang around until it either becomes a brown dwarf, or flies through enough matter to his the Chandrasekhar limit, then KABOOM!
In addition to everything else mentioned, in your scenario, you would also need to pull 2 neutrons from somewhere. A helium nucleus has 2 protons and 2 neutrons, but each H nucleus (generally) is just 1 proton. The 2 neutrons are critical in holding nuclei together.
That’s why nuclear fusion uses deuterium and tricium, isotopes of hydrogen with respectively one and two neutrons. These are much rarer than regular hydrogen, but can be found in some water molecules known as “heavy water”. They can be separated from the other molecules with a centrifuge since they’re heavier. Two deuterium atoms would produce Helium 4, but that’s not the most efficient fusion, and thus not the one that they plan to use in fusion reactors. Instead, they fuse a deuterium and a tricium, resulting in an Helium 5 atom. Unlike regular helium(4), helium 5 is radioactive, but it’s got a relatively short half-life and will soon expell it’s extra neutron, creating the helium we know and love.
