Lunar eclipse Wednesday night

Lunar eclipse Wednesday night

Lunar eclipse Wednesday night

Bad Astronomy
The entire universe in blog form
Feb. 19 2008 1:00 PM

Lunar eclipse Wednesday night

By now you've probably heard about the lunar eclipse tomorrow night. Lunar eclipses are great; they last a long time, so there's no hurry, you don't need crystal clear skies (the clearer the better, of course), and you don't need a telescope! Just your eyes will do, though having binoculars is better. I actually prefer them over using a telescope.

The event will be visible pretty much everywhere in the US, Canada, South America, and western Africa and Europe. Orbiting Frog has a ton of info, including a nice animation of what to expect. Sky and Telescope has info as well (including a diagram with times listed for the west coast of the US, if that helps). But here's the rundown:

Phil Plait Phil Plait

Phil Plait writes Slate’s Bad Astronomy blog and is an astronomer, public speaker, science evangelizer, and author of Death From the Skies!  

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The show starts for real around 01:43 Universal Time (CAREFUL HERE! That's 1:43 a.m. on Thursday morning in England, but that's Wednesday night for the United States. Check to see what your local offset is from Universal Time; for example, in Boulder we are UT - 7, so the eclipse starts here at 1:43 a.m. UT - 7 hours = 6:43 p.m. local time Wednesday night. But don't trust me-- do this math for yourself!).

You may read that the eclipse starts an hour or so before that, but if you look you probably won't see anything. Earth casts a dark shadow surrounded by a much lighter one, called the umbra and penumbra, respectively. When the Moon enters the penumbra you'll hardly notice, but when it enters the umbra at 01:43 it'll look like a bite is taken out of it.

1 hour 20 minutes later (03:00 UT) the Moon will be totally engulfed in the Earth's shadow. It may take on a brown or reddish appearance, depending on various factors like pollution in our atmosphere. Sometimes the Moon turns blood red, and it's really amazing. I have found that the Moon appears to really be a globe when this happens; I assume it's an illusion of some kind but the effect can be overwhelming.

The totality phase of the eclipse will last for about 51 minutes, and then it will start to leave the umbra, and you'll see a bright crescent begin to form. By 05:10 UT it'll all be over, and the Moon will look normal again.

I plan on being at The Little Astronomer's school, since they're hosting a party in the parking lot to see it. There are no doubt viewings all over the place, so call your local astronomy club, museum, or even news station to see what's going on in your area.

This is the last total lunar eclipse for the US until very late in 2010, so I hope you get a chance to see it!