I'm pretty sure there's some mistranslation of the five elder's names going on and that in reality all 5 have names (codenames?) after 5 planets. We have Mars and Saturn, I'm 99.9% sure that two of the others are supposed to be Jupiter and Mercury, though I'm unsure what "Nusjuro" is meant to be. Considering the other 4 I'd assume logically Venus but I have no idea.