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2024 Mar 24: Penumbral Lunar Eclipse  (2023-12-09) ⬅︎
Starting at 9:53 PM (PT) on March 24 and ending at 2:32 AM on March 25, a penumbral lunar eclipse will be occurring. This type of eclipse can be hard to detect unless you are looking for it because the moon only darkens a bit.

To understand this, first imagine sunlight shining on the earth. The earth, of course, blocks some of the light which creates a shadow that extends into space beyond the earth. The shadow is a bit complex in that it has two parts -- a central umbra that is red since earth's atmosphere scatters the blue light that grazes its edges. Surrounding the umbra is a much lighter penumbra which is more neutral in color.

Most people are aware of total lunar eclipses in which the moon travels into the umbra and turns a dark red. But, with a penumbral lunar eclipse, the moon travels only into the penumbra.

During the eclipse most of the Moon (96%) will enter the penumbra (see above) and it will dim. Many people might not even notice the difference from a normal Full Moon. But if you look closely, you'll see and you'll know. Good luck!

Be sure to check out our Star Guide feature with its tools for knowing what's out each night and where to look.