Hitting Send

I am feeling very excited about the full lunar eclipse. Lunar eclipses occur when the moon passes through the Earth’s shadow. Since this occurs only when the moon is on the far side of the Earth from the sun, lunar eclipses only happen when the moon is full. The shadow of Earth will creep across the face of the brightly lit full moon for more than an hour before totality (the total phase) occurs. The total phase will last approximately 50 minutes.

There are three types of lunar eclipses: penumbral, when the moon crosses only the Earth’s penumbra; partial, when the moon crosses partially into the Earth’s umbra; and total, when the moon crosses entirely within the Earth’s umbra. Total lunar eclipses (as we’re about to have) pass through all three phases. Even during a total lunar eclipse, however, the moon is not completely dark. Sunlight refracted through the Earth’s atmosphere intersects the umbra and provides a faint illumination. Much as in a sunset, the atmosphere tends to scatter light with shorter wavelengths, so the illumination of the moon by refracted light has a redish hue. Recent volcanic eruptions in South and Central America may cause the eclipsed moon there to take on a black, blue, or violet hue.

It will be visible from western Europe and Africa, all of South America, and central and eastern North America. Unfortunately the full eclipse will not be visible in eastern Asia or Australia. One does not need special equipment to view the eclipse, nor does one need to take special precautions, as it is perfectly safe to view with the naked eye. NASA suggests using binoculars to enhance viewing. The next full lunar eclipse does not occur until December 21, 2010! A couple of partial and penumbral eclipses will occur between now and then. The moon will already be in eclipse phase during the moon rising for the western US, including Alaska. For those on the west coast, it will begin at about 7:01pm. For the east coast at 10:01pm and ends just after midnight February 21st. Europeans will view it on the 21 February. Don’t miss it! Enjoy my friends!