I already did some previous researches and found a lot of explanations about the differences between "dark and "darkness", including answers to a question here in StackExchange, but I'm still in doubt about which one to use in some situations - and it's also hard to be sure when they are interchangeable or not.
For instance, in the sentences below is the use of "dark" correct (or acceptable) or should I use "darkness" instead? Or maybe both words can be used without changing the meaning of the sentence.
Can you see that strange light blinking in the dark? It’s being up there for more than an hour and none of us have any idea about what it may be.
And, even with all those clouds in the sky, we were still able to see that tiny star shining far away in the dark.