Eclipses are very exciting events, special moments that provide beautiful visual spectacles in the sky. Every year there are typically two to three eclipses of the Sun ("solar eclipses") and two to three eclipses of the Moon ("lunar eclipses"). And for each eclipse the event can be "total" (where the Sun or Moon is fully blocked out), or "partial" where a portion of the Sun or Moon is blocked out, but a portion is still visible.
Last month there was one such event, a type of solar eclipse called an Annular Eclipse. In this configuration, the Moon's disk appears to block out most the Sun but does not completely block it out. What makes the Annular Eclipse very special, however, is that the disk of the Moon is fully encircled by the Sun. The eclipse in January was not visible here in San Francisco but was seen in the eastern hemisphere. A fellow astronomy blogger and resident of Sri Lanka, Desh, put together an eclipse page that has video footage of the event and lots of great photographs. He organized a major eclipse viewing event for Sri Lanka.
Throughout 2010 there are more eclipses. The biggest event of the year is the Total Solar Eclipse that happens this July 11th, but again will not be visible here in San Francisco. To see this one you will need to travel to the South Pacific. The NASA Eclipse web site is full of details on this and every eclipse and for those of you who want to travel to see a Total Solar Eclipse someday, consult the NASA Total Solar Eclipse Paths map on their website. I think of it as a long-range travel planner!
For those of us in the Bay Area (and the entire Western Hemisphere), mark your calendars for December 21st when we get a beautiful Total Lunar Eclipse on the solstice to welcome in the winter.
Note: for a nice audio description of an eclipse, listen to my recent interview on KALW (just after the stargazing part of the interview).