The Umbra is completely dark. Partially Dark is Penumbra.
it is called the penumbra
Lunar eclipse: Earth makes the shadow; the moon passes through it.Earth's shadow is large enough to darken the shole moon at the same time.Solar eclipse: Moon makes the shadow; earth passes through it.Moon's shadow is not large enough to darken the whole earth at the same time ...it causes only a small dark spot, that moves along the surface as the earth turns.
The umbra in a shadow is the portion where light from a source is completely blocked. This is in the middle of the shadow. The area around this, where light from part, but not all of the source shines is called the penumbra. In the shadow cast by the moon in an eclipse, the penumbra is the partial shadow that occurs before the total eclipse, and the umbra is the 'total eclipse' portion
The darker complete shadow is the "umbra". The lighter partial shadow is the penumbra.
There are to parts that are less darker than the Umbra. One is called the Penumbra, that's where you see part of the light source, and the other is called an Antumbra, this is similar in effect to the Corona seen in a Solar Eclipse. But the largest part is the Penumbra.
That part of the shadow is called the penumbra.
The penumbra.
The "umbra" is the dark area of complete shadow. Around it is the "penumbra", which is partial shadow.
The penumbra.
penumbra cats a dull shadow. Umbra cats dark shadow.
penumbra