Eclipsed Moon

Taking a break from Game 4 of the World Series on October 27, 2004, Sky & Telescope editor in chief Rick Fienberg snapped this view of that evening's total eclipse of the Moon.

After a drought of 2½ years, we can finally look forward to a total lunar eclipse on the evening of March 3, 2007. On that night the Moon gradually slides into and out of the shadow cast by Earth in space. It is one of the grandest and most beautiful events in nature!

We haven't had a total lunar eclipse since October 27, 2004 — which coincidentally took place during the decisive Game 4 of the World Series between the Boston Red Sox and the St. Louis Cardinals! Yet March 3rd's event will be the first of three total lunar eclipses to take place within the next 12 months.

Unlike a solar eclipse, which you have to view through a special protective filter to protect your eyes, a lunar eclipse is easy to see with any filter. And you don't need any special equipment to view it — you can watch it with your eyes alone. But using binoculars or a small telescope will make the viewing experience more rewarding.

March 3rd lunar eclipse

A lunar eclipse occurs when the Moon passes through the shadow cast by the sunlit Earth (diagram not to scale). It has two components: the outer, lighter penumbra and the inner, much darker umbra. Click on the image for a larger view.

Sky & Telescope illustration by Gregg Dinderman


We see lunar eclipses when Earth passes directly between the Sun and the Moon. This geometry creates two kinds of shadows on the lunar surface. Within the outer shadow, the penumbra, the Moon is bathed in a slightly smoky cast; an astronaut standing on the lunar surface would see the Sun partly covered by Earth. Penumbral shading can be difficult to detect, especially near the beginning or end of an eclipse.

As the Moon begins to move into the central and darkest part of Earth's shadow, the umbra, you'll notice an obvious and ever-larger "bite" in the lunar disk. The partial eclipse is then under way. (A partial eclipse also happens when the Moon glides only part way through the umbra.)

On March 3rd, however, the Moon dives completely inside the umbra, and once that happens no rays of sunlight can reach the lunar surface directly. Even so, the Moon may glow with an eerie coppery light in the night sky, because some sunlight is refracted through the atmosphere all around Earth's circumference, and some of this reddened light faintly illuminates the Moon.

March 3rd eclipse map

The total eclipse on March 3rd favors viewers in eastern North America and Europe. For those west of the Mississippi River, totality ends before moonrise. Click on the image to see the entire map.

S&T illustration

Check the map at right and the table below to find out if the eclipse is viewable from your location. If you live in the eastern U.S. and Canada, you'll see the eclipse in progress at nightfall. Only in New England, Québec, and the Maritime Provinces does the sky become fully dark before the end of totality. Farther west, the eclipse is nearing its end when the Moon rises, and the Sun sets — unfortunately, the main event ends before moonrise for anyone west of the Rockies. Farther east, across the Atlantic Ocean, the entire eclipse can be viewed from Europe, Africa, and western Asia, where it occurs in the hours before dawn on March 4th.

If you're east of the Mississippi River, you'll see the Moon rise while still in totality. But you may find it very difficult to spot the lunar disk at all while it's still very low in the sky. So, if your weather permits, note where moonrise occurs along the horizon on the evening before the eclipse; on March 3rd the eclipsed Moon will rise very close to that location.

Total Eclipse of the Moon, March 3, 2007
Eclipse stage AST EST CST MST PST
Partial eclipse begins 5:30 p.m
Total eclipse begins 6:44 p.m. 5:44 p.m.
Total eclipse ends 7:58 p.m. 6:58 p.m. 5:58 p.m.
Partial eclipse ends 9:12 p.m. 8:12 p.m. 7:12 p.m. 6:12 p.m.
Last shading visible? 9:50 p.m. 8:50 p.m. 7:50 p.m. 6:50 p.m.

Observers in the northeastern U.S. with binoculars or a telescope will get a bonus: while the Moon is totally eclipsed, its edge will occult (cover) the 5th-magnitude star 59 Leonis. Then 20 minutes to over an hour later, depending on your location, the star will suddenly reappear on the Moon's upper-right edge. Predicted local times for the disappearance and reappearance for 10 major northeastern North American cities are on a special web page for this event. The southern edge of the region of visibility (the graze line) crosses central Virginia.

It’s relatively easy to take photographs of a lunar eclipse. Modern digital cameras can record exposures long enough to capture the Moon even when it’s completely inside the umbra.

Camera close to eyepiece

You can try recording the eclipse by holding your camera directly over the eyepiece of binoculars or a telescope. For added stability, use the camera's ¼-20 socket to attach it to a tripod.

Sky & Telescope photo by Craig Michael Utter

However, it’s important to use enough magnification. An ordinary point-and-shoot film camera will produce an image of the Moon too small to record even as much detail as you can see with your unaided eye.

The minimum focal length for getting a good-looking image of the Moon is about 300 mm. Few people own telephoto lenses this long. But if you have a telescope, your local camera store should have the adapters needed to couple your SLR (detachable-lends) camera directly to your telescope. Or you can give your camera a magnification boost simply by putting it close to the eyepiece of either binoculars mounted on a tripod or a small telescope. Go to our online article for expert tips on how to photograph a lunar eclipse.

Two other total lunar eclipses occur within the next 12 months: the one on August 28, 2007, favors viewers in western North America and Canada; the Moon sets just after it fully enters the umbra for most viewers on the Atlantic Coast. An eclipse on February 20, 2008, should be viewable in the evening for virtually everyone in North America.

You'll find a complete guide to viewing the March 3rd lunar eclipse in the March/April issue of Night Sky magazine, now on newsstands.

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