The next performance of light and shadow by the Earth-Moon-Sun trio takes place Wednesday morning when the Earth passes between the sun and moon creating a "penumbral lunar eclipse."
In a penumbral lunar eclipse, the moon falls under the dim edge, or penumbra, of the Earth's shadow, instead of the main part of the shadow called the umbra. As a result, the moon's face grows a bit dimmer instead of showing a clearly defined disc moving across it as can be seen in a regular lunar eclipse.
The eclipse will peak around 6:33 a.m. Pacific time, and should be detectable between 6-7 a.m., according to Nasa. Unfortunately for Los Angeles area residents, fog or clouds may spoil your view of the penumbral eclipse, according to Anthony Cook, who writes the Sky Report for the Griffith Observatory. Partly cloudy skies are forecasted for the Los Angeles area overnight and during the peak of the eclipse.
"It really all depends on the clouds," Cook wrote in an email to Patch. "The full moon, of course, is the easiest of all things to find at night. The eclipse will dim one side of it noticeably, but it will still be quite bright at mid-eclipse at 6:32 a.m., minutes before moon-set. The forecast is for cloudy conditions after midnight, which is still six hours before the eclipse is visible, so I'd say the chances are slim for a good view.
If the clouds end up in L.A.'s favor, Cook recommends a westward view and a pair of binoculars.
"In case it is clear, the best locations will have a clear view of the horizon to the west-northwest," Cook wrote. "Hills or buildings in that direction will obscure the view of mid-eclipse and moon-set. Assuming that clouds were not a factor, the best locations around LA include hillsides with a clear view to the west, or westward facing beaches (Santa Monica to Seal Beach)."
Here's Cook's description of the penumbral eclipse from the Griffith Park Observatory:
The waxing moon changes from crescent to first quarter phase on Tuesday the 20th, and is full on Wednesday, November 28. On that date, the moon will undergo a penumbral eclipse, an excursion through the fuzzy outer shadow of the earth. This will result in a shading of the upper portion of the moon that you should be able to see by 6:00 a.m., during the dawn while the moon is sinking toward the west-northwest horizon. The maximum eclipse at 6:32 a.m. is only 5 minutes before the moon sets as seen from Los Angeles. Then, 92 percent of the moon will be in the penumbra, and the moon’s top edge should appear quite dark compared to the lower edge. Although unrelated to the eclipse, this will also be the year’s smallest full moon, 12 percent smaller than average. This is because the full phase is falling on the same date as the apogee, the farthest distance that the moon’s elliptical orbit takes it from us. This is the opposite condition that produced the “super moon” we all heard about last May.
The eclipse will not be visible from the Eastern seaboard of the United States since it will occur after moonset there.