NERVAfan

I severely doubt that they'll have discovery for the stuff that's already in the game. The planets out to Saturn were known before telescopes. (Uranus was discovered in 1781 and Neptune in 1846, also well before the Space Age, but they don't have KSP equivalents yet). Eeloo is hard to find an analogue to, really, but it would certainly have been discovered before the Space Age, as far more distant Pluto was (1930). And if it's to become a moon of the Saturn-analogue, the big moons of Saturn were known quite early (the closest analogue, given that Eeloo is supposed to get cryovolcanism, is likely Enceladus - discovered 1789). Even quite small moons were known - Amalthea of Jupiter, and Phobos and Deimos of Mars, were discovered in the late 19th century. And Bop and Pol are not even all that small - 65 and 44 km radius according to the wiki, which with the KSP space-compression factor would make them nearly 700 km and over 450 km in our Universe, quite significant bodies.

Ah, thanks.

As for algae creating the oxygen: could still be possible even with radiation, depending on how intense the radiation is. There are Earth microbes that can survive really intense radiation. And maybe Laythe has a super greenhouse effect atmosphere, rich in methane ... and maybe it has sulfur hexafluoride (supposedly 16000 times stronger than CO2 as a greenhouse gas) or something.

Laythe is a city inside the Moon in Edgar Rice Burroughs' The Moon Maid. The "Mohole" project is named for the Mohorovicic discontinuity, so yeah, it's the same idea.

I've seen people posting pictures online of bases on Kerbin, but... how do they do this? Once I land something on Kerbin, I can't go to the Space Center without Ending Flight, so how do you leave something "active" on Kerbin to connect more stuff to later?