The brightness of the moon's red glow depends upon how much dust and clouds are in the Earth's atmosphere, following volcanic activity Ash can block out enough light to render the moon a darker red or even mere black.
To help you focus, norepinephrine creates a sort of tunnel vision, blocking out surrounding distractions, possibly even warping your sense of time, and enhancing your memory.
And I think that's why it has really helped improve my focus in general, because being able to block that out and go internal in terms of what you're imagining is a really, really useful skill.
Try to be more conscious of what your shallow tasks are, and give yourself permission to block them out for a while so you can focus on the important tasks that require 'deep work'.
You can completely block out all outside sound, or you can turn it down and let in some outside sound if you need to talk to a colleague or hear traffic, or whatever.