If its a total lunar eclipse why does one edge remains brighter than the rest?
I have been googling for an answer for a while and cant find it. Even pictures of previous total lunar eclipses are the same. Is it because that side remain closer to the edge of the umbra? Or is it caused by how light behaves; Or because the surface of the moon is more reflective on that part.
For a solar eclipse, to my knowledge, it’s just a happy accident that our moon is pretty much the right size to block out our sun. Isn’t that neat? A solar eclipse on every other planet in the solar system would end up being much less interesting.
Sorry, thats not my question. I misstyped solar instead of lunar so I take the blame.
But I agree that its quite amazing how perspective wroks between the sun, earth, and the moon. Earth is also the right size tho block out the sun the same way when viewed from the moon. Would be hard to believe if we werent experiencing it tbh.
Unfortunately solar eclipses are going to get less neat over time, because the moon is gradually moving away from the earth.
But that’s going to take thousands or millions of years, so in your lifetime it probably will still look just as neat.
The alignment is not perfect. The shadow of the earth entirely covers the moon - as the earth is bigger.
This is the answer. The moon is passing through phases as it orbits and isn’t perfectly aligned so there will always be shading and color variations.
I’m posting this video because they animate the different types of eclipse and also explain why it’s red. So now it’s just understanding that everyone’s view is always “off to the side” so there is a gradient of color and brightness.
I get that, but if the moon is completely behind the umbra of earths shadow why is that it looks brighter on one side/edge?
Examples:



Not my pictures btw. I took them from r/astrophotography
Go out on a sunny day. Get in the shadow of a building - near the edge. Notice that you can know when the sun is close to becoming visible by the scattered light. One side is brighter.
Now imagine being in orbit of earth. Watch the sun set behind it. You see the sky glowing in the direction of the sun. Same as the building. Same as regular sunsets.
Now go to the moon. Because of the extreme distance, you can see the “sunset” entirely around the globe. That is the red glow. But one side of the moon is closer to the sunset, and (just like the building) that side is brighter.
Does that help?
I think it does. Thanks.
So in other words; That side of the moon is closer to the edge of earths shadow. Correct?

