Late Monday night/early Tuesday morning, the moon will be passing through earth’s shadow. It’s called a lunar eclipse, and it’s a wonderful astronomical show. There are no tickets to buy, though you might need an alarm so you wake up to catch it. Oh yeah, and some lack of clouds. As of right now, it’s not looking too promising. But the Finger Lakes is a quilt of microclimates and the big weather services don’t seem to do a good job for predicting the weather in lowly little rust-belt Geneva. Sometime I think they give us the forecast for Rochester or Buffalo, both of which lie in the normal lake-effect snowbelt. Geneva doesn’t. But I digress. It will either be clear or not. If it is, it’s worth taking a walk outside to catch some of the action.
The eclipse officially begins at 12:55 EST (aka Finger Lakes Time), when the moon’s leading edge enters the penumbra, or outer shadow of the earth. By the way, that’s AM. As in, put the kids to bed and set an alarm. This eclipse is not for the weak of constitution. At 1:33 AM the edge will enter the umbra, and the partial eclipse will have begun. The penumbra is a gradual transition and the first parts of it don’t really have a visible effect on the moon’s appearance. At what point between 12:55 and 1:33 do you notice the moon darkening?
The moon will enter the umbra, or inner shadow of the earth, at 2:41am, and it will stay there until 3:53am. NASA recommends that if you have only one moment to look at the eclipse, it should be 3:17am, when the moon is deepest in Earth’s shadow. What color will it be? It’s often a deep rusty red color, but it depends on the earth’s atmosphere; given all the volcanic activity in the last year, sunrises and sunsets have been more colorful, and that should (literally) reflect on the moon. The color you see on the moon during totality is a reflection of the ring of sunsets/sunrises a lunar explorer (were she present on the moon tomorrow night) would see as the earth passes in front of the sun. You know that sailing expression, red sun at night, sailor’s delight, red sun in the morning, sailor take warning…well, what if you see both at once? I’d say check your air supply and head back to the base before you push your luck.
The whole show is over between 5:15 and 5:30. When can you last see a trace of the earth’s penumbra on the moon?
The lunar eclipse, if the weather gods give us a reprieve from the clouds, is a great and easy way to touch base with the universe. You don’t really need anything to watch it except your eyes and some warm clothes. If you’ve got binoculars or a telescope, have at it, but this is one of the universe’s displays that people can enjoy with just their eyes.
For those of you watching your calendar, or you pagans out there who think you know the true meaning of Christmas (or at least, it’s timing in the calendar), tomorrow is the Winter Solstice. The coincidence of the eclipse and the solstice is just that, a coincidence. No, it’s not further evidence of the Mayan Apocalypse, so don’t pick up the phone and dial Mel Gibson just yet. Here’s what NASA has to say about the coincidence:
This lunar eclipse falls on the date of the northern winter solstice. How rare is that? Total lunar eclipses in northern winter are fairly common. There have been three of them in the past ten years alone. A lunar eclipse smack-dab on the date of the solstice, however, is unusual. Geoff Chester of the US Naval Observatory inspected a list of eclipses going back 2000 years. “Since Year 1, I can only find one previous instance of an eclipse matching the same calendar date as the solstice, and that is 1638 DEC 21,” says Chester. “Fortunately we won’t have to wait 372 years for the next one…that will be on 2094 DEC 21.”