@Kaffe@chitter.xyz A lot of rockets use RP1 (basically highly refined kerosene) and liquid oxygen, because liquid hydrogen has some big disadvantages (notably that it's big... very low density, need really big tanks, and also that it's cryogenic)
i don't know if they do anymore but red fuming nitric acid used to be used as an oxidizer instead of liquid oxygen too, for the same reason--it's liquid at room temperature and atmospheric pressure
needless to say RFNA is nasty stuff environmentally speaking
-F
@Kaffe@chitter.xyz Some historical rockets also used monomethylhydrazine (MMH) or unsymmetrical dimethylhydrazine (UDMH) which on top of being horrendously toxic, produce all manner of nasty combustion products
and then there was the hydrogen/lithium/fluorine rocket that was tested once and never actually used because seriously what the fuck
-F
@Kaffe@chitter.xyz oh not just historical, apparently the Proton rockets still use UDMH in combination with dinitrogen tetroxide, another oxidizer I forgot to mention. they probably have a ton of nitrogen oxides in their exhaust
RP1/LOX is, i think, the most common fuel/oxidizer mixture though. I know the Falcon rockets use that, and a lot of NASA's rockets have and do as well
-F
@Felthry @Kaffe a lot of the CSNA rockets also use N2O4, which is why the smoke coming off of crashed boosters and stuff is orange, though they're moving more towards hydrolox now