Synopsis
Early next week (Mon night), there will be an unusual eclipse. Here’s additional information so that you can plan to see it. The weather forecasts have been varying, but there’s a chance the rain will clear enough that evening to see it.
“On the night of December 20-21st, 2010, a total lunar eclipse will dress the moon in holiday red for more than three hours. For 72 minutes of that eclipse, the Earth’s shadow will hide the moon in complete darkness. This unusual celestial event is visible for hundreds of millions of viewers across North America. The last year North America saw a total lunar eclipse on the winter solstice was 1638. The next is 2094 – making this event a once-in-a-lifetime opportunity.” (from http://www.southernstars.com/eclipse)
“Lunar eclipses happen when the full moon passes through the shadow of the Earth. Because the moon?s orbit is tilted compared to the Earth?s orbit around the sun, most full moons miss the shadow entirely.” (Griffith Observatory)
NASA has a good deal of information available at: http://www.nasa.gov/topics/solarsystem/features/watchtheskies/index.html
Full Details
“The eclipse occurs on the longest night of the year, and its maximum is only about fifteen hours before winter begins. It is also the highest in the sky that a totally eclipsed Moon has appeared from Los Angeles in 1,591 years and it will not be this high again for at least another millennium.” (from http://www.griffithobservatory.org/exhibits/special/Special_Event_Lunar_Eclipse.html)
More details from http://www.griffithobservatory.org/skyreport.html
Griffith Observatory will be open to the public between 8:00 p.m. Monday night, the 20th, until 1:30 a.m. Tuesday morning, the 21st, during the eclipse. In addition to planetarium shows and special lectures, our telescopes will be joined by those of the Los Angeles Astronomical Society and the Sidewalk Astronomers for free eclipse viewing. In case of bad weather, we will try to show streaming Internet video of the eclipse from clear locations. The next total lunar eclipse will be seen from Los Angeles on December 10, 2011.
You can begin to see the alignment that leads to the eclipse at sunset Monday evening. If you have a clear horizon, you will see the full moon rising in the east-northeast at the same time that the sun sets in the west-southwest. From Los Angeles, sunset is at 4:55 p.m. At 9:27 p.m., P.S.T., the eastern (left-hand) edge of the moon reaches the fuzzy outer shadow (penumbra) of the Earth, although this shading is too subtle to see right away, but careful observers may see a slight darkening by about 10 p.m. At 10:32 p.m., a much darker bite appears on the moon?s east edge. This is the start of the umbral eclipse. The eclipse becomes total at 11:40 p.m. The moon does not disappear completely, however, but usually remains visible with a red or coppery tint, due to sunlight bent and filtered by our atmosphere into the umbra, bathing the moon with an eerie glow. Over the next 73 minutes, the color and brightness of the moon will change as light passes through different storms, volcanic eruptions and other atmospheric conditions along the Earth?s limb as seen from the moon. Totality ends at 12:53 a.m., and the moon emerges completely from the umbra at 2:01 a.m. The theoretical end of the eclipse, when the moon comes out of the penumbra, is at 3:06 a.m., but it is unlikely that you will see any shading after 2:30 a.m.
Because this eclipse comes only about 13 hours before the start of winter, when the sun is farthest south, the full moon is nearly as far north as it can be. Because the moon is totally eclipsed when it crosses Griffith Observatory?s meridian at 11:50 p.m., it will be the highest above the horizon that a full moon has appeared in the sky from this location since December 18, A.D. 419, and is higher than any eclipse will appear from here through the year A.D. 3000!
No equipment is needed to observe the eclipse, but binoculars and telescopes definitely help. While the eclipse is enjoyable from urban or suburban settings, observers in dark wilderness locations can also enjoy seeing the surrounding Milky Way appear as the sky darkens around the subdued moon. Weather-forecasting websites should be consulted to find alternate observing locations in case of iffy weather.
The official star of winter is at 3:38 p.m., P.S.T. on Tuesday, December 21. This is when the sun is farthest south in the sky, and the day is shortest-9 hours, 53 minutes from Los Angeles.
Jupiter is the brilliant object visible in the evening, while Saturn and the brightest planet, Venus, are prominent in the southeast before dawn.