Starting late Monday night into early Tuesday morning, the Western Hemisphere will get a magnificent show. The moon will pass through the Earth’s umbra (shadow). This is called a Lunar Eclipse (sometimes referred to as a “Blood Moon”). When the eclipse begins, the moon will begin to darken slightly as it starts to encounter the shadow. As the shadow begins to “cover” the moon, a reddish-brown or rust color will be seen on the moon. The reason for this discoloring is because light is being refracted through the atmosphere of the earth. This same effect is why we see a dark orange or red sun at sunrise and sunset.
This eclipse is special because we will be in the prime viewing area for the eclipse. All of North America along with much of the Pacific Basin will be able to see the Full lunar eclipse during the scheduled times for that time zone. The entire event begins at 9:53 p.m. Monday night. The West Coast will be able to view the eclipse darkening starting at 10:57 p.m. on Monday night. This will be the “partial” stage where the shadow will start to become visible. The total phase (darkest stage) will occur between 12:06 a.m. and 1:24 a.m. on Tuesday, with the midpoint occurring at 12:45 a.m. The entire eclipse will end at about 2:33 a.m. The only drawback is that clouds will be moving into the area before a storm system that will pass on Tuesday, therefore viewing may be difficult. If you happen to be in an area that is covered with clouds, NASA will be broadcasting the entire eclipse on their website.
Lunar eclipses only occur when the moon is in its “full” stage and the sun, earth and moon all align perfectly for the shadow to be cast. What’s special about this particular eclipse is that it is the first in a tetrad of eclipses. A tetrad is a group of four. Over the next two years we will see four lunar eclipses starting with the one occuring Tuesday. The other three are scheduled for: October 8th 2014, April 4th 2015, and September 28th 2015.
As a lagniappe: There will be two other notable events happening at the time of the eclipse. Look out for Spica (the brightest start in the constellation Virga), as it will be very close, visually, to the moon during its eclipse. Plus, Mars is still in opposition making it orange hued and star-like. It will be visible to the west of the eclipse.