Update (2/20): Overcast. Bleh.
If you’re under cloudless skies this coming week be sure to take a look outside between 8 and 9 pm (Central Time) on Wednesday, February 20th. There is expected to be a beautiful total lunar eclipse which will be visible over all of the Americas. If you miss this one, you won’t have another chance until 2010.
The eclipse will begin when the moon enters the faint outer portion, or penumbra of the Earth’s shadow. The penumbra, however, is all but invisible to the eye until the moon becomes deeply immersed in it. Sharp-eyed viewers may get their first glimpse of the penumbra as a delicate shading on the left part of the moon’s disk about 20 minutes before the start of the partial eclipse (when the round edge of the central shadow or umbra, first touches the moon’s left edge). During the partial eclipse, the penumbra should be readily visible as a dusky border to the dark umbral shadow.
The moon will enter Earth’s much darker umbral shadow at 1:43 on Feb. 21 by Greenwich or Universal time, which is 8:43 p.m. on Feb. 20 in the Eastern time zone, 7:43 p.m. Central time, 6:43 p.m. Mountain time and 5:43 p.m. Pacific time.
Seventy-eight minutes later the moon is entirely within the shadow, and sails on within it for 51 minutes (about average for a total lunar eclipse), until it begins to find its way out at the lower left (southeastern) edge.
The moon be completely free of the umbra by 9:09 p.m. Pacific time or 12:09 a.m. (Feb. 21) Eastern time.
The vaguer shading of the inner penumbra can continue to be readily detected for perhaps another 20 minutes or so after the end of umbral eclipse. Thus, the whole experience ends toward 12:30 a.m. for the East (with the re-brightened moon now sloping down along the high arc it describes across the sky), or during the mid-evening hours for the West.
I was able to see the partial eclipse that occurred in March, and I hope that the weather will cooperate and I will be fortunate enough to see this one. The universe truly is a wonderful and beautiful thing.
Related: Lunar Eclipse