Guide to Planetology?

[Azrael]

So I started my game for the first time and since I have a knack with dense forests and jungles, I looked at the Planet Classes and saw the Hydra Class.

But when I progress so far to roll for the Biosphere, I almost always get Human Atmosphare Hazard Rating "Insidious", only a very few times I got "Imperfect", however I aim for No Atmospheric Hazards for Humans.

And the few times I got "Imperfect", these were not lush green forests but muddy brown, autumn-like forests.

Are Hydra Class Planets meant to never have a perfect breathable atmosphere or am I doing something wrong?
I try to aim for around or more than 1 AU so it has a somewhat earth-like distance. Tilt, the other value of importance, afaik only deals with how extreme the Seasons are (if there are seasons at all) so this shouldn't have an influence on the atmosphere.

PS: I experimented a bit more, am I right in my conclusion, that you need atleast a gravity of around 0,45 g to have a chance to get an earth-like atmosphere?
It seems to me, that Hydra Class Planets get at max 0,4 g generated, never seen one with more than 0,4 g.

[Azrael]

I tried now with Medusa Class planets until I got a planet with an "earth-comparable atmosphere" and about 350 mm/year rainfall.

And when I proceed to Biosphere, I still get Insidious Atmospheric Hazards.

I dunno but "Earth-comparable" would mean in my eyes I get high levels of N2 and O2 and a bit of Argon, probably not in the very same mix as on earth, so maybe something like 60% N2, 35% O2 and the rest the other ones (earth has 78% N2, 21% O2 for comparison).

But when I proceed with the "Earth-comparable", I get like 70+x% Argon or a majority of NOx or stuff like that. That is not Earth-comparable imho, that is highly toxic or "Insidious" as the game calls it.

So I don't get, where this "Earth-comparable" comes from, does this purely relate to atmosphere density or what?

[maerchen]

I just ignore breathing hazards and aim for terran farming.

Breathing hazards give your militia and army envirosuits which come with a defense bonus over just uniforms. Open world farming is guaranteeing unproblematic food resource production.

pages 153 +159 manual for reference.

[Thomas]

In beta 1.08.02 Vic has increased chance of having good atmo in Hydra class planets.