penumbrae

Example:Sky enthusiasts were able to observe a penumbral lunar eclipse on the night of the full moon.

Definition:A type of lunar eclipse where the Moon passes through the Earth's penumbra, resulting in a subtle darkening of the Moon.

Example:Artists often use penumbral radiance to create dramatic lighting effects in their paintings.

Definition:A term describing the softened light or shadow that surrounds a fully defined shadow.

Example:Research in the intellectual penumbra of computer science can lead to unexpected innovations and discoveries.

Definition:A broad, less defined area of knowledge or discourse that surrounds the core field of study, often including related topics.