Weather permitting, there may be no better place than Dane County for watching tonight's total lunar eclipse, which will be visible across much of North and South America as well as certain other regions of the world. The local forecasts at this writing predict clear to partly cloudy skies, which would afford fine viewing. Temperatures are expected to plunge toward the lowest yet this winter, however, so pile on the insulating layers if you intend to step outside to see what may prove quite a spectacular display.
Depending on conditions, a total lunar eclipse can light up the moon in colors ranging from rich orange or red to deep brown or luminous charcoal as it traverses earth's shadow.
From Madison and the rest of Dane County, the partial eclipse will begin at about 7:43 p.m. The moon will enter total eclipse at about 9:01 p.m. and exit about 50 minutes later, lingering in partial eclipse until a few minutes past 11 p.m. The Madison Clear Sky Clock forecasts clear conditions through this period.
Total lunar eclipses are not all that rare, but they don't happen often enough that you can take them for granted. (I've seen no more than a handful, and count myself fortunate.) In some years, such as 1982, there are as many as three; in other years, zilch. The last one visible here in Madison occurred on Aug. 28, 2007, and spent an hour and a half in totality. The next total lunar eclipse visible from Madison and vicinity is expected on Dec. 20, 2010.
But the clouds don't always cooperate, and life is short: If you live another 30 years and stay here in Dane County all that time, you might see 19 more total lunar eclipses (assuming the clouds part for every occasion). Live to mid-century and you'll have a shot at viewing 28 from these parts, tops.
Lunar eclipses also enjoy certain advantages over solar eclipses. One can, for example, look right at a lunar eclipse and watch it from start to finish without burning one's retinas to a crisp and going blind -- a hazard of solar eclipses that can spoil the spectacle and lead to a lifetime of regret.
More information on tonight's total lunar eclipse, including charts, data, explanations, history and advice on watching and photographing the spectacle is available from NASA and Sky & Telescope Magazine, while "Mr. Eclipse" Fred Espenak offers primer on lunar eclipses.
In lieu of the sun's warmth, a thermos filled with tea, coffee, chocolate or other hot beverage might be in order as an added buffer against temperatures that could drop below zero right about the time tonight's total lunar eclipse reaches its midpoint.