January 1981 lunar eclipse

Penumbral lunar eclipse January 20, 1981

A penumbral lunar eclipse took place on Tuesday, January 20, 1981, the first of two lunar eclipses in 1981. In a rare total penumbral eclipse, the entire Moon was partially shaded by the Earth, and the shading across the Moon should have been quite visible at maximum eclipse. The penumbral phase lasted for 4 hours and 24 minutes in all, though for most of it, the eclipse was extremely difficult, if not impossible to see. The moon's apparent diameter was larger because the eclipse occurred 5.2 days after perigee.

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