If a human were on the ground (at the right spot) on the Moon when the Earth eclipsed the Sun, would they see anything particularly spectacular? Or would it just look like a sort of hole in space where the Sun used to be?
It would look like looking at the nightside of the Earth, with no visible sunlight or sun. The Earth, viewed from the Moon, is four times larger in diameter than the Moon appears from Earth, so the Sun is likely to be completely occluded in short order, for more than an hour.
You will see the atmosphere of Earth glowing red because of refracted sunlight, which is the same reason the surface of the moon seems to turn red in a lunar eclipse (exactly the same event, but from Earth’s perspective).
The Wikipedia article has a video that depicts how one of these would look.
I traced the video back to its origin at NASA, so here it is directly:
I think an important point to note is, because the moon has no atmosphere, it is easy to see the sun’s corona any time the sun is visible. You could just cover the solar disk with your thumb and you’d see the corona. (I think this is correct.)
Cool. And what an interesting question.
given the lack of atmosphere, and the clarity that goes with it - would it be possible to see light produced by the big metros e.g. NYC-Philly-Baltimore-Washington corridor ?
that’d be kinda cool
As Arthur C. Clarke so poetically put it (I can’t recall in what story) when you look from the moon at the red atmospheric corona around the earth during such an eclipse, you are seeing “all the sunsets and sunrises on the Earth at once.”