Isay it is penumbra
You're talking about the "penumbra" of the shadow. There's nothing mysterious
about it really. It's just the area on the earth's surface from which you can see a
part of the sun but not all of it.
(Answered as "What travels across the surface of the Earth when an eclipse occurs?") The shadow of the Moon travels across the Earth during a Solar Eclipse. (During a Lunar Eclipse, the shadow of the Earth travels across the Moon.)
During a total eclipse, it is called the path of totalityAn Eclipse.
During a solar eclipse, the shadow of the MOON falls on the EARTH.
The umbra ans penumbra
Isay it is penumbra
eclipse
An eclipse. When the Earth is in the Moon's shadow, it's a solar eclipse; when the Moon is in the Earth's shadow, it's a lunar eclipse.
The umbra of the Earth's shadow during lunar eclipse is larger than the umbra of the Moon's shadow during a solar eclipse because the Earth is much larger than the Moon is; so, the Earth's shadow is bigger than the Moon's shadow.
an eclipse.
eclipse
It's the Earth's shadow.
If you can see the solar eclipse, then you are in the Moon's shadow.