I think it's penumbra. It's the area around something.
penumbral shadow of the moon.
Definitely. First as the Moon passes through the Prenumbra of the Earth it will darken. Then as it goes through the Umbra it will become a copperish red.
The "penumbra" of the earth's shadow consists of everywhere in space behind the earth from which you could see part of the sun but not all of it, because the earth itself covered part of the sun from your view.
The US Constitution listed a set of un-enumerated rights that were thought to be so basic that they did not need to be listed as other rights were. These rights are often called penumbra's which means Obscure, but in law means implied. For instance, many claim "Free Speech" based on the First Amendment; while the First Amendment gives no right of "Free Speech" - the right of free speech to any individual is implied.
Oh, dude, it's like super simple. So, the Earth rotates on its axis, right? And that rotation is what gives us day and night. When one side of the Earth is facing the sun, it's daytime there, and the other side is in the dark, so it's nighttime. It's like a giant game of peek-a-boo with the sun.