Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.astronomy.net/forums/observation_reports/messages/250.shtml
Дата изменения: Unknown
Дата индексирования: Sun Apr 10 02:42:39 2016
Кодировка:

Поисковые слова: universe
Total Lunar Eclipse May 15-16 - an Astronomy Net Observation_reports Forum Message
Back to Home

Astronomy Discussion Forums

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button

Home | Discussion Forums
Login

Total Lunar Eclipse May 15-16

Forum List | Follow Ups | Post Message | Back to Thread Topics
Posted by Bob Sal on April 29, 2003 17:49:05 UTC

Hi All;
There’s an excellent event coming in May not to be missed. A total Lunar Eclipse. On the night of May 15-16 the Earth will come between the Sun and the Moon casting a shadow that will slowly cover the Moon. This is a thrill a minute event, especially if you’ve never witnessed one before. Starting at around 9:00 PM the Moon enters the Penumbra phase. You won’t see much yet. The real action starts just after 10:00 PM when the Eclipse begins. You’ll start to see a small bite take out of the Moon on the side near the bottom. This will grow larger and larger until the entire Moon is covered. It will take about 1 hr and 15 minutes. If we’re lucky and the sky is clear the Moon will turn a beautiful copper color during totality. The last total Eclipse was on a day where it snowed 10” all day. About 10 minutes after the Eclipse started the snow stopped and the sky cleared. 20 minutes later it clouded again and then it cleared during totality. It stayed clear for the duration of the event. Did I mention the actual temperature was –3 degrees that night with a wind chill of, well I think it was off the chart and powdery snow blowing all over the place. I got about 15 minutes of video during the short partial phase that was visible. To video tape this event, you can just point your video camera into the eyepiece. Of course there are better ways but you’d be surprised how good a video you can get with a small scope, video camera and tripod.
Let me point out a few things I found fascinating about the total Lunar Eclipse you may want to look for. First, the shadow moves quite fast. If you go inside and come back in 10 minutes you’ll see a change. Next, normally when you view the Moon through a telescope, along the terminator you see exquisite shadows cast from the mountains that gives it that 3D effect we all love. During the Eclipse, what resembles the terminator, is not. It’s a shadow being case on the Moon so the mountains do not cause shadows. It’s a completely different image than what you would normally expect to see. Very cool! Notice the shape of the shadow crossing the Moon. It’s curved. Why? When early astronomers realized the Moon was not disappearing for some magical reason, it was just a shadow do to the geometry of the situation, this proved the Earth was round. So if you know anyone who still thinks the Earth is flat, make sure they see this. Next, use your minds eye and imagine a huge wall behind the Moon. Extrapolate the curved image on the Moon to a full circle to get a feel for the size of the complete shadow of the Earth. If you can get to a pretty clear location with an unobstructed view, notice where the Moon is and where the Sun is. Use both arms to make a straight line from the Moon to the ground through the Earth in the direction of the Sun. It’s pretty much a straight line. Move one arm in the direction the Sun is going and the other in the direction the Shadow is going. Now make a noise like a chicken (just kidding, couldn’t help myself). If you ask me, this gives you a unique prospective on exactly where you are standing in space. Lastly, and I missed this last time so it’s something I’ll be looking for. During the partial phase you can’t see the part of the Moon that’s cover by the shadow at all. Yet during the total phase the entire Moon is visible as this wonderful copper color. At some point the invisible part covered by the shadow during the partial phase must reappear and turn copper. Exactly when does this happen? All at once? Very slowly? To be continued…..

That’s it;
BOB SAL

Follow Ups:

Login to Post
Additional Information
Google
 
Web www.astronomy.net
DayNightLine
About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
Unless otherwise specified, web site content Copyright 1994-2016 John Huggins All Rights Reserved
Forum posts are Copyright their authors as specified in the heading above the post.
"dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
are trademarks of John Huggins