Christmas Eclipse

Last minute Christmas shoppers may want to pick up solar filters for the science enthusiasts on their gift list this weekend because on Christmas day, a partial solar eclipse will darken parts of North America. Just after sunrise on December 25, residents of the Pacific northwest and western Canada will experience the eclipse--after which its shadow will slowly move east, hitting the Atlantic coast between 12:30 p.m. and 1 p.m. Fred Espenak has worked out exact timetables for the United States, Canada and Latin America.

The most dramatic coverage of the Sun by the moon--a full 72 percent--will occur at 12:23 Eastern Standard Time, although only people on Baffin Island in northern Canada will see so much of the Sun obscured. In the northeast of the U.S., the eclipse will reach a magnitude near 60 percent, whereas in the far southwest it will be less than 20 percent. Remember that you should never look directly at the Sun with the naked eye or through an unfiltered telescope or binoculars. Doing so can cause permanent eye damage. You should use special glasses, or project the image through a properly shielded optical instrument or onto a piece of paper through a pinhole. For additional details on these viewing methods, see How to Watch a Partial Solar Eclipse Safely from Sky & Telescope magazine.