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Old 18-January-2008, 06:17 PM
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Centaur Centaur is offline
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Wink Total Lunar Eclipse - 2008 FEB 20/21

A total lunar eclipse will occur during the night of 2008 FEB 20/21. As with any Full Moon, it will be visible from the entire nighttime side of the Earth. Most or all of it will be seen in the Americas, Europe and Africa.

The maximum magnitude in the umbra will be 1.105. That means during totality the greatest separation between the edge of the umbra (dark portion of Earth’s shadow) and the nearest point on the limb of the Moon will be 10.5% of a lunar diameter. The greatest possible magnitude is 1.881.

This will be the last total lunar eclipse until 2010 DEC 21, although there will be three partial lunar eclipses between now and then.

Below are my predictions for the various stages of the event in Universal (Greenwich) Time. I use the French Rule for shadow sizes and know of no other source that takes into account the oblate shape of the Earth.

00:37 UT – Moon enters penumbra (gray fringe shadow)
01:43 UT – Moon enters umbra (dark inner shadow)
02:18 UT – 50% of Moon’s diameter covered by umbra (magnitude 0.500)
03:01 UT – Totality begins (magnitude 1.000)
03:26 UT – Maximum eclipse (magnitude 1.105)
03:51 UT – Totality ends (magnitude 1.000)
04:34 UT – 50% of Moon’s diameter covered by umbra (magnitude 0.500)
05:09 UT – Moon exits umbra (dark inner shadow)
06:16 UT – Moon exits penumbra (gray fringe shadow)

I’ve created graphics that illustrate the stages of the eclipse as seen from Arlington Heights, Illinois and London, England. They should well serve most observers in North America or Europe. They can be seen by clicking: http://www.curtrenz.com/astronomical.html

Photos and descriptions of the eclipse would be welcome additions to this thread.
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Last edited by Centaur; 17-February-2008 at 11:48 PM. Reason: Title amendment
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Old 10-February-2008, 05:38 PM
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Folks in India, Australia and New Zealand have been asking me if they'll be able to see the upcoming lunar eclipse. Sorry, but the eclipse will occur during daytime for observers at those locations while the Moon is beneath the horizon.
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Old 12-February-2008, 02:31 AM
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Quote:
Originally Posted by Centaur View Post
I’ve created graphics that illustrate the stages of the eclipse as seen from Arlington Heights, Illinois and London, England.
Thanks for the details Centaur. I'm in the same neck of the woods. Two of my children were born in Arlington Heights.

(No, I don't want to buy anything, Thank you)
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Old 12-February-2008, 05:58 PM
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Would this be visible from the Atlanta area?
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Old 12-February-2008, 06:03 PM
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Quote:
Originally Posted by Paradox244 View Post
Would this be visible from the Atlanta area?
Yes. (The date on the graphic is the UT date.)

February 2008 AstroCalendar

Dave Mitsky
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Old 12-February-2008, 06:06 PM
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Originally Posted by Paradox244 View Post
Would this be visible from the Atlanta area?
Yes, it will be visible to anyone experiencing nighttime (and clear skies) while the eclipse is taking place. For EST (Eastern Standard Time) either subtract 5 hours or add 19 hours to the UT (Universal Time) timings that I gave in my initial post.
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Old 18-February-2008, 07:47 PM
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Wink Lunar Eclipse - Chicago's Aldler Planetarium - Feb 20

Joe Guzmán who operates the Chicago Astronomer website will be hosting a public gathering outside Chicago's Adler Planetarium on Wednesday evening February 20 to view the eclipse. Bring your telescope or look through those brought by others.
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Old 18-February-2008, 08:07 PM
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Quote:
Originally Posted by Paradox244 View Post
Would this be visible from the Atlanta area?

Lunar eclipses should be visible anywhere on earth where the moon is above the horizon during the progression of the eclipse. At full moon of eclipses, these places should be dark enough
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Old 19-February-2008, 12:07 PM
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The eclipse is right next to Saturn. Will it be close enough to Saturn to enable photography of Saturn and part of the eclipse with any detail of the rings?
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Old 19-February-2008, 04:12 PM
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The eclipse is right next to Saturn. Will it be close enough to Saturn to enable photography of Saturn and part of the eclipse with any detail of the rings?
That's an excellent question. As viewed from Chicago the centers of the Moon and Saturn will be separated by 3.9° at the moment of maximum eclipse. That’s about 8 lunar diameters. Since you have not given your location, I cannot supply a better figure for you. The Moon is so close that parallax matters. In any event, the low magnification required to get them both in the same field of view would not likely make Saturn’s ring detail apparent. Interestingly for some South American observers, the bright star Regulus will be occulted by the Moon during the initial penumbral phase of the eclipse.
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Old 19-February-2008, 11:03 PM
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Quote:
Originally Posted by Centaur View Post
That's an excellent question. As viewed from Chicago the centers of the Moon and Saturn will be separated by 3.9° at the moment of maximum eclipse. That’s about 8 lunar diameters. Since you have not given your location, I cannot supply a better figure for you. The Moon is so close that parallax matters. In any event, the low magnification required to get them both in the same field of view would not likely make Saturn’s ring detail apparent. Interestingly for some South American observers, the bright star Regulus will be occulted by the Moon during the initial penumbral phase of the eclipse.
Thank you. I live in Australia so will not see the eclipse. Will the sun's rays during totality appear to extend to the position of Saturn? If so it could be a good project for astrophotography to see how Saturn appears during the eclipse tonight.
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Old 19-February-2008, 11:30 PM
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Thank you. I live in Australia so will not see the eclipse. Will the sun's rays during totality appear to extend to the position of Saturn? If so it could be a good project for astrophotography to see how Saturn appears during the eclipse tonight.
You’re welcome, Robert. Yes, the Sun’s rays will continue to reach Saturn. Saturn cannot be eclipsed in Earth’s umbra. I’m certain that many folks will photograph the eclipsed Moon and Saturn in a single frame. But as I noted above, the field would be so wide that Saturn will not appear as much more than a dot. Nevertheless, it would be nice to see the images.

It is possible for Earth to transit the Sun as viewed from Saturn. In that case Earth would appear to be a tiny speck on the Sun and would not be cutting off many of the rays otherwise destined for Saturn. I calculate that the next such transit will occur on 2020 JUL 20. The last one was on 2005 JAN 13.
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Old 19-February-2008, 11:33 PM
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Default Re: Total Lunar Eclipse - 2008 FEB 20

Quote:
Originally Posted by Robert Tulip View Post
Thank you. I live in Australia so will not see the eclipse. Will the sun's rays during totality appear to extend to the position of Saturn? If so it could be a good project for astrophotography to see how Saturn appears during the eclipse tonight.
Not sure what you're asking.

If you mean, will the lunar eclipse have some sort of visual effect on Saturn, then the answer is no, since Saturn is located off-axis from the Sun-Earth-Moon alignment.

However, the Sun's rays always extend to Saturn. That's what makes it visible from Earth. Even if the Earth and Moon were directly in front of the Sun, whether during a lunar eclipse or not, there'd be almost no effect of Saturn's brightness, since, as seen from Saturn, the Earth-Moon system would be a tiny dot(s) against the solar disc. Sort of like how there's no appreciable decline in solar magnitude during a transit of Mercury as seen from Earth.

Note: written while Centaur was writing and posting.
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Old 19-February-2008, 11:57 PM
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Visible from the South Pole? The Sun is not currently visible from the North Pole so I don't believe the Moon is from the South. sorry penguins
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Old 20-February-2008, 12:59 AM
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Old 20-February-2008, 01:11 AM
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Old 20-February-2008, 01:37 AM
Robert Tulip Robert Tulip is offline
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Quote:
Originally Posted by Maksutov View Post
Not sure what you're asking. If you mean, will the lunar eclipse have some sort of visual effect on Saturn, then the answer is no, since Saturn is located off-axis from the Sun-Earth-Moon alignment. However, the Sun's rays always extend to Saturn. That's what makes it visible from Earth. Even if the Earth and Moon were directly in front of the Sun, whether during a lunar eclipse or not, there'd be almost no effect of Saturn's brightness, since, as seen from Saturn, the Earth-Moon system would be a tiny dot(s) against the solar disc. Sort of like how there's no appreciable decline in solar magnitude during a transit of Mercury as seen from Earth. Note: written while Centaur was writing and posting.
Sorry, that was dumb of me. I was confusing with a solar eclipse where the sun's corona is visible around the moon. Of course there is no corona on a lumar eclipse.
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Old 20-February-2008, 06:14 PM
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http://sunearth.gsfc.nasa.gov/eclips...2008Feb21.html
I found this website by NASA with these pretty pictures showing how it will be for many timezones. Thought it would be helpful to put it up here, it helped me.
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Old 20-February-2008, 06:42 PM
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Originally Posted by ravens_cry View Post
http://sunearth.gsfc.nasa.gov/eclips...2008Feb21.html
I found this website by NASA with these pretty pictures showing how it will be for many timezones. Thought it would be helpful to put it up here, it helped me.
Thank you, ravens_cry. While the NASA text does show the timings for different time zones, every one of the diagrams utilizes equatorial coordinates in which celestial north is up. Such diagrams often confuse folks who expect the eclipse shadowing to first and last appear on the Moon at positions other than the ones actually observed. That’s why I create diagrams using horizontal coordinates in which zenith is up.
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Old 20-February-2008, 06:59 PM
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It will be at the times shown though, right? I think I will be able to find the moon, unless these clouds don't clear up. Dang! we had a clear day yesterday.
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Old 20-February-2008, 07:09 PM
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