Regions Of Earth’s Shadow – The Penumbra Eclipse

We all know that the Sun shines light on the Earth and unless it is 12 O’clock noon everything casts a shadow. Did you know that the Earth also casts a Shadow? When Sunlight reaches the Earth, the surface of the Earth facing the Sun is illuminated and the opposite surface is dark. The Dark area is the Earth’s shadow. The Earth’s Shadow has two parts, the Umbra and the Penumbra. The Umbra is the center of the shadow where it is so dark it looks black. The Penumbra is the outer edges of the shadow and is so light that it looks gray.
A Penumbra Eclipse is a type of lunar eclipse. A Penumbra Eclipse is sometimes confused with a Partial Lunar Eclipse because a part of the moon crosses the Umbra while a part of the moon crosses the Penumbra. A true Penumbra Eclipse occurs when the entire moon crosses only the Earth’s lighter shadow, or Penumbra. If the moon, while within the Penumbra, passes close to the Umbra it will look like a dark shadow crosses the moon. Unfortunately, if the moon is too far away from the Umbra the moon will look like any other moon.