A total lunar eclipse visible from five continents occurs after sunset Wednesday when the full moon orbits into the shadow of the Earth and slowly turns from a bright silver into a copper or orange disk. More than a billion people will have a chance to watch as the moon appears to be slowly nibbled away, changing from the normal bright reflected light of a full moon into the colorful glow of eclipse. The celestial show starts at 8:23 p.m. EDT over the United States and will end about 5{ hours later. The eastern United States will get the best viewing and Alaska will miss the eclipse altogether. Visible eclipse phases will vary for the central and western parts of the country because of the difference in sunset and moonrise. In Los Angeles, for instance, the eclipse will have started before the sun has set or the moon has risen. By the time the sky has darkened completely in California, the moon will already be in the deepest part of its eclipse. For Seattle, the moon will still be below the horizon at mid-eclipse, but will rise during the totality phase. Clouds, of course, could ruin the viewing at any location. With clear skies, though, some phase of the celestial spectacle should be visible to observers in North and South America, western Europe and Africa, and the Antarctic. Sailors at sea in the Atlantic and in the eastern Pacific Ocean also will be able to see part of the eclipse, weather permitting. A lunar eclipse occurs when the moon passes through the shadow created by the Earth blocking the sun's light. The moon, in its orbit of the Earth, usually passes above or below this shadowline, but every few years it follows a path that puts it completely in shade for a time. When the whole moon passes through the shadow, it is called a total eclipse. The last total lunar eclipse visible over most of North America occurred in December 1982, and the next one is not until December 1992. Astronomers are forecasting that Wednesday's eclipse may be a bright one. The moon can appear during an eclipse to be a bright coppery red if there is clear, clean air between the lunar surface and the observer on Earth. If smoke or dust obscure the view, the moon will diminish to an orange color or perhaps even fade from view altogether. Volcanic eruptions historically have dimmed eclipse viewing by dumping tons of dust into the atmosphere. But astronomers say enough time has passed since the last major volcanic eruption that most dust has settled. The eclipse starts when the moon enters what is called the penumbra. This outer fringe of the Earth's shadow will show up on the moon as a grayish shading. After about half an hour, the moon will edge into the umbra, the dark, central part of the shadow. Total eclipse, when all of the moon is covered by the umbra, will begin at about 10:20 p.m. EDT and last for one hour, 36 minutes. When the moon leaves the umbra, the events will occur in reverse order. The eclipse ends about 1:53 a.m. EDT when the moon edges out of the shadow altogether. While a lunar eclipse occurs when the Earth blocks sunlight from the moon, a solar eclipse is caused when the moon blocks sunlight from the Earth. To experts, a solar eclipse is more interesting because it permits unique measurements of the sun. ``Solar eclipses attract a lot of scientific attention,'' said John Bangert, a U.S. Naval Observatory astronomer in Washington. ``A lunar eclipse is just a good show.'' Here is when the various phases of the eclipse will occur. All times are Eastern daylight. Moon enters penumbra: 8:23 p.m. Moon enters umbra: 9:21 p.m. Moon enters totality: 10:20 p.m. Middle of Eclipse: 11:08 p.m. Moon leaves totality: 11:56 p.m. Moon leaves umbra: 12:56 a.m., Thursday. Moon leaves penumbra: 1:53 a.m. Because of the differences in sunset and moonrise times, viewing will start at different eclipse phases in the western parts of the country. Here are times for the local events that affect eclipse viewing. The first hour is for local sunset and the second is for local moonrise. The best viewing will follow twilight which ends about 25 minutes after sunset. Local time zones apply in all cases: Baltimore: Sunset at 8 p.m. Moonrise at 7:53 p.m. Boston: 7:43 p.m. and 7:36 p.m. Chicago: 7:49 p.m. and 7:43 p.m. Cleveland: 8:25 p.m. and 8:18 p.m. Houston: 8:01 p.m. and 7:55 p.m. Kansas City, Mo.: 8:12 p.m. and 8:06 p.m. Los Angeles: 7:39 p.m. and 7:35 p.m. Philadelphia: 7:56 p.m. and 7:48 p.m. Salt Lake City: 8:24 p.m. and 8:20 p.m. San Francisco: 8:01 p.m. and 7:58 p.m. Seattle: 8:20 p.m. and 8:16 p.m. St. Louis: 7:54 p.m. and 7:47 p.m. Washington: 8:01 p.m. and 7:54 p.m.
A total lunar eclipse visible from five continents will occur Wednesday, beginning at 8:23pm EDT and ending 5 hours later. The eastern United States will get the best viewing, but it also will be visible to observers in South America, western Europe, Africa and the Antarctic. A lunar eclipse occurs when the moon passes through the shadow created by the Earth, blocking the suni's light. The last total lunar eclipse visible over most of North America occurred in December 1982, the next one will be in December 1992. Total eclipse, when the entire moon is covered by the central part of the shadow, will begin at about 10:20 pm and last one hour and 36 minutes.