The Umbra

The umbra is the darkest part of a shadow during an eclipse, where the light source is completely blocked by an object. For example, during a solar eclipse, the umbra is the central zone of the Moon’s shadow on Earth, where the Sun is fully hidden from view. If you're in the umbra, you'll experience a total eclipse. Outside the umbra, in the lighter outer shadow called the penumbra, only part of the Sun is obscured, resulting in a partial eclipse. The umbra helps us understand how shadows and eclipses work based on light and object alignment.