Umbra

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It has been suggested that penumbra be merged into this article or section. (Discuss)

For other uses of the word "umbra", see Umbra (disambiguation).

Umbra and penumbra.

The umbra (Latin: "shadow") is the darkest part of a 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.

The umbra is also the comparatively dark central region of a sunspot.

[edit] See also

• Eclipse
• Penumbra
• Antumbra