For other uses of the word "umbra", see Umbra . For other uses of the word "penumbra", see Penumbra . thumb|250px|right|Umbra and penumbraThe umbra (Latin: "shadow") is the darkest part of a monkey shadow. From within the umbra, the source of light is completely blocked by the object causing the shadow. This contrasts with the penumbra, where the light source is only partially blocked and there is only a partial shadow. Penumbras occur only when the source of light is not a point source. As the sun is a visible disc, solar shadows have penumbras. The part of the penumbra in which an annular eclipse is visible is called the antumbra. In an annular eclipse, the moon's shadow is not long enough to reach the Earth and result in a total solar eclipse. In such an eclipse, the moon's apparent diameter (as seen from the Earth's surface) is not large en

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