We're not suppose to see the sunrise and sunset in underground, did we?

Is a simple question, if you guys know what I said, just don’t understand how can the PC still seen the sunrise and sunset in underground, how could they know that without a watch? memory or something?

Do you have a watch? Maybe your character kind of knows when the sunset is supposed to happen? It still shouldn’t happen in the final version though.

Still can’t explain how could you character still remember the time when they a sleeping and wakeing in underground, and no watch, of course.

This is minor, but makes sense.
I think that intended behaviour would be to lose sense of time a while after going underground (3-8 hrs).
Adding some kind of ‘memory’ attribute to the player perhaps could have other uses too.