WAUKESHA, WISCONSIN: People in Alaska and Hawaii have front-row seats for one of nature’s more impressive spectacles: a partial solar eclipse. Late on the afternoon of October 13, the Moon will slide slowly in front of the Sun, eventually blocking up to 90 percent of our star from sight. Those with clear views to the west and southwest will see the Sun set with a large bite removed from it.
The action starts in northeastern Asia the morning of October 14. The Moon’s shadow first touches Earth’s surface in central Russia. Later that morning, residents of Japan, Korea, western China, and Siberia will see the partial eclipse. The farther north you live, the better the view. People in Japan will see up to 40 percent of the Sun covered, while those in eastern Siberia will notice 60 to 80 percent of the Sun blocked.
The action then shifts to Alaska and Hawaii the afternoon of the 13th. (No, Earth doesn’t pass through a time warp – the eclipse begins October 14 and ends on the 13th because the Moon’s shadow crosses the International Date Line.) People in western Alaska will get the best view. As the Sun dips toward the horizon, the Moon will cover more than 90 percent of its face. Viewers will see a thin crescent Sun, with the cusps of the crescent pointing up. Eclipse viewing precautions
Unfortunately, the opportunity to see an eclipse also brings risk. The Sun shines so brightly that it can blind anyone who looks at it directly – even when the Moon hides most of it from view. Even worse, the damage happens both quickly and painlessly.
That doesn’t mean you shouldn’t watch the eclipse, just that you need to take proper precautions. One safe method is to view the Sun indirectly by projecting its image. You’ll need two pieces of white cardboard, some aluminum foil, tape, and a stickpin. Cut a hole in one piece of cardboard and tape the foil over the hole. Then use the pin to poke a tiny hole through the foil. During the eclipse, stand with your back to the Sun and let sunlight pass through the pinhole onto the second piece of cardboard, where an image of the eclipsed Sun will appear.
You can view the eclipse directly by using a safe solar filter. A #14 welder’s glass works fine – look for it at a welding supply store. Mylar or metal-on-glass filters sold through astronomy-equipment suppliers also will allow you to view the eclipse safely.
You should never use a so-called Sun filter that screws into the eyepiece of a telescope. Also, avoid using sunglasses, smoked glass, photographic film, black plastic garbage bags, Mylar candy wrappers, or photographic neutral-density filters. Although these materials may limit the amount of light that passes through, they do little or nothing to stop the equally harmful infrared radiation. Hawaii
Observers in Hawaii also contend with sunset arriving around the time of maximum eclipse. If you can find a location where the ocean forms your western horizon, so much the better. From Honolulu, the eclipse gets underway at 5:14 P.M. Hawaiian Time (11:14 P.M. EDT) and reaches its peak when the Sun sets at 6:06 P.M. (12:06 A.M. EDT, Thursday, October 14). The Moon then hides about half the Sun from view. From the Big Island, the Sun sets about 10 minutes earlier, with the eclipse not quite at its maximum extent. Alaska
From Nome, the eclipse begins at 5:42 P.M. Alaska Daylight Time (9:42 P.M. Eastern Daylight Time) and greatest eclipse comes at 6:49 P.M. (10:49 P.M. EDT). The Sun sets at approximately 7:45 P.M. (11:45 P.M. EDT), with the concluding phases of the eclipse still underway. From both Anchorage and Fairbanks, the Sun sets before the eclipse reaches its maximum. Still, approximately three-quarters of the Sun will be blocked as it reaches the horizon. Remember: If mountains limit your line of sight, the Sun will hide behind the horizon earlier and less of it will appear eclipsed. It will pay to find a spot with an unobstructed horizon to the west and southwest.
October 11, 2004