@AndrewHartman Definitely, thanks for bringing that up.
I'll steal the 90% number. This is part of a series of chat-gpt generated markets, but my understanding is the only realistic way a planet like this would be found today is via spectroscopy. Having no astronomy creds, I have no idea what sort of confidence those measurements come with. 90% seems as good as any other arbitrary point.
@VerySeriousPoster I'm not an astronomer either, but I do follow some of the exoplanet stuff - I think 90% is a feasible number, while still being a reasonably high bar.
@BrunoParga Good point, sorry for missing the notification for this comment.
I'll use the following criteria:
Atmospheric pressure that humans can withstand without specialized equipment
Temperatures that allow for humans to walk somewhere on the surface without specialized equipment. This does not need to be universal (the Earth has plenty of places that are inhospitable), but if there is any amount of space where a human would be comfortable with no more than normal clothing this criteria will be met.
Water
I don't include breathable atmosphere, since that seems like an unrealistically high bar.
@VerySeriousPoster Yeah, it's unlikely we'd be able to tell whether the atmosphere is actually breathable within the resolution of this question.