Full moon winter solstice arrives with total lunar eclipse Dec. 21

December 18, 2010

Image courtesy NASA.

Best viewing for our area should occur at 2:17 a.m. CST

A special treat for sky watchers occurs in the early morning hours of Dec. 21 as the winter solstice arrives with a full moon and lunar eclipse. The last lunar eclipse of 2010 is especially well placed for observers throughout North America. The eclipse occurs at the moon’s descending node in eastern Taurus, four days before perigee.

The entire event is visible from North America and western South America. The Moon’s orbital trajectory takes it through the northern half of Earth’s umbral shadow. Although the eclipse is not central, the total phase still lasts 72 minutes. The Moon’s path through Earth’s shadows as well as a map illustrating worldwide visibility of the event are shown here
The timings of the major eclipse phases are listed below.
Penumbral Eclipse Begins: 11:29:17 CST
Partial Eclipse Begins: 12:32:37 CST
Total Eclipse Begins: 1:40:47 CST
Greatest Eclipse: 2:16:57 CST
Total Eclipse Ends: 2:53:08 CST
Partial Eclipse Ends: 4:01:20 CST
Penumbral Eclipse Ends: 5:04:31 CST

At the instant of greatest eclipse (2:17 CST) the Moon lies near the zenith for observers in southern California and Baja Mexico. At this time, the umbral magnitude peaks at 1.2561 as the Moon’s southern limb passes 2.8 arc-minutes north of the shadow’s central axis. In contrast, the Moon’s northern limb lies 8.1 arc-minutes from the northern edge of the umbra and 34.6 arc-minutes from the shadow center. Thus, the southern half of the Moon will appear much darker than the northern half because it lies deeper in the umbra. Since the Moon samples a large range of umbral depths during totality, its appearance will change dramatically with time. It is not possible to predict the exact brightness distribution in the umbra, so observers are encouraged to estimate the Danjon value at different times during totality (see Danjon Scale of Lunar Eclipse Brightness). Note that it may also be necessary to assign different Danjon values to different portions of the Moon (i.e., north vs. south).

The Emerald Coast Meditation Society will be meeting at the beach is Seaside next to Bud & Alley’s at 2 a.m. Weather permitting, they will meditate from 2 – 2:30 a.m. Bring warm wraps and something to sit on. Members Caroling and Nancy from will be there from about 1:45 till 2:45 a.m.