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[–]magnora7 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (2 children)

I was reading about rocket fuel, and even the best hydrocarbons (ones the most dense with hydrogen, like methane usually) produce a theoretical maximum output of energy per kg that is about 1/3rd of pure H2 hydrogen. Nothing can get near it except nuclear technology which is like 100x better, but that carries its own very serious risks.

Look at the difference in this chart:

https://upload.wikimedia.org/wikipedia/commons/4/4f/Specific-impulse-kk-20090105.png

[–]Chop_Chop[S] 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (1 child)

Interesting chart, thanks, I hadn't seen that before. Another chart, energy density

https://upload.wikimedia.org/wikipedia/commons/thumb/c/c6/Energy_density.svg/1080px-Energy_density.svg.png

Look at where Li-Ion is vs. H2

[–]magnora7 2 insightful - 1 fun2 insightful - 0 fun3 insightful - 1 fun -  (0 children)

Wow yeah nothing can touch it in terms of energy density by both weight and volume.

The next step up seems to be ionic thrust. And the next step after that is nuclear. There's so much research going on with ionic rocket engines, it's a very interesting technology.