Wow, those stars are amazing at altitude and with no light pollution, I wish the passengers could see up too (and also without a nose-greased, scratched-up plastic in between).
Those photos are eight to thirty second exposures at f/2.8 and ISO >10k - there's a lot more light in the pictures than a human eye can ever gather. I'm sure the sky would still look pretty epic to a completely dark-adjusted eye, though.