Monday, February 18, 2008

It's only two more days to go until the one and only lunar total lunar eclipse of 2008 visible from North America. There won't be another total eclipse visible from our area until 2010.
So far the viewing conditions look quite good. as the time draws closer I urge readers to consult the Clear Dark Sky Website for viewing conditions in their locality. So far they only give projected conditions up until the early hours of Wednesday. The Clear Dark Sky site covers the entire continent of North America, and gives much more detailed and precise information than you will get on the usual weather report. For the weather report here in Canada you are best to consult the Environment Canada site. this forecast goes a little bit further out on a limb than the CDS site is willing to, but it is less detailed than the former (for viewing conditions) and only covers Canada. From what I see on their satellite mpa predictions Wednesday evening here in Winnipeg will have a gradually increasing cloud cover but will be fairly clear in the early hours of the eclipse. Well, we all know not to put too much faith in such projections. Consult both this site and the CDS one closer to the actual event.
When the eclipse occurs you will be treated to an additional bonus. The planet Saturn, which spends the month of February in the constellation Leo, will be about a close 3.5 degrees above and to the left of the eclipsed Moon (as seen from North America) at mid-totality (3:26 UT, 21:26 CST) . As the Moon moves through the various parts of the eclipse you will see it changing its position vis-a-vis Saturn. You will also see the apparent brightness of Saturn increase as the light of the Moon fades during the eclipse, and decrease again as the Moon becomes more visible as the eclipse recedes. Saturn's point of opposition will occur on February 24, but its greatest brilliance (magnitude +0.2) has already occured on February 16. The difference between this and the present magnitude will be insignificant. Saturn will end its retrograde motion on March 2. The present tilt of Saturn's rings is about -8.4 degrees as seen from Earth. they are thus not optimally oriented for viewing, but are still visible. See if there is any difference in their visibility in mid-totality as compared to full Moonlight.
Molly has previously given the times of the various parts of the eclipse in both Universal Time (UT) and here in Winnipeg in Central Standard Time (CST), but this obviously bears repeating. See below. Conversion to your local times can be done by consulting the Time and Date website. Pretty well all of the western hemisphere will be able to view all the parts of the eclipse (though the Moon will rise on the west coast partially eclipsed already).The Time and Date website also gives the times of Moonrise and Moonset. So here are the times once more, in UT and CST.
*Penumbral eclipse begins: 00:36 UT, February 21/19:43 CST, February 20.
*Partial eclipse begins: 1:43 UT, February 21/19:43 CST, February 20.
*Total eclipse begins: 3:01 UT, February 21/21:01 CST, February 20.
*Maximum totality: 3:26 UT, February 21/21:26 CST, February 20.
*Total eclipse ends: 3:50 UT, February 21/21:50 CST, February 20.
*Partial eclipse ends: 5:08 UT, February 21/23:08 CST, February 20.
*Penumbral eclipse ends: 6:15 UT, February 21/00:15 CST, February 21.

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