Today, or rather, at the end of yesterdays session, I discovered that the Moon (from Galacticraft) has an over 2 hour night cycle! After landing there. In the middle of said night cycle.
At least I brought along equipment to make oxygen.
I also discovered that torches extinguish themselves without oxygen.
So I'm current sitting on the moon, in the near darkness, with a bunch of equipment set up to make oxygen, hoping the single Advanced Energy Cube I brought along doesn't run out before the sun hits the solar power plant feeding it. Because I cannot get into the Rocket without refueling it and there are evolved creepers out there.
EDIT: Having looked it up, the day-night cycle lasts, in total, 2 hours 40 mins.