Off topic but please forgive ....

[Maury Siskel <maurysis@ev1.net>]

http://www.space.com/spacewatch/eclipse_041027.html



Link above for complete article plus diagrams



Last Chance Until 2007: Total Lunar Eclipse Tonight!

By Robert Roy Britt <mailto:rbritt@hq.space.com>

Senior Science Writer

posted: 27 October 2004

06:42 am ET



Skywatchers on half the planet are gearing up to watch Earth's shadow 

consume a blood-red Moon tonight in the last total lunar eclipse until 2007.



Weather permitting, the easy-to-watch event will be visible across most 

of North and South America, Western Europe and Africa. It will be 

webcasted <http://www.space.com/spacewatch/041022_eclipse_guide.html> 

live from several locations, and glimpses might be televised 

<http://www.space.com/spacewatch/041022_eclipse_series.html> during Game 

4 of the World Series.



The eclipse begins at shortly after 8 p.m. ET (5 PT), but the first hour 

or so won't be noticeable as the Moon becomes lightly shaded by Earth's 

outer shadow, called the penumbra. Things get real interesting at 9:14 

p.m. ET (6:14 PT, when the Moon begins sliding into Earth's full shadow, 

or umbra.



A dark and growing scallop will then gradually envelop Earth's only 

natural satellite. Once in total shadow at 10:23 p.m. ET (7:23 PT), the 

Moon might turn a shade of deep red that frightened the ancients. No two 

eclipses are alike, however, and astronomers can't say for sure what 

color to expect, if any.



What's going on



Lunar eclipses occur when Earth's shadow prevents sunlight from 

reflecting off the Moon. They can only occur during full Moon, and only 

on the relatively rare occasions when the Moon's orbit carries it into 

the same plane of space as Earth's path around the Sun.



The schedule is predictable but somewhat erratic.



There have been four total lunar eclipses during the past 18 months, but 

there won't be another one until March 3, 2007.



During totality, when the Moon is completely immersed in shadow, it 

might turn red, the result of Earth's atmosphere bending hints of all 

the world's sunrises and sunsets simultaneously onto the Moon while the 

Sun's primary light is blocked.



Totality lasts until 11:45 p.m. ET (8:45 PT).



"The Moon will never be completely dark," explained Charles 

Schweighauser, professor of astronomy and physics at the University of 

Illinois at Springfield.



"The color of the Moon in shadow will range from a coppery color to dark 

red, depending on the amount of dust and water vapor in the Earth’s 

atmosphere."



Easy to watch



Telescopes are not needed to enjoy a lunar eclipse, but binoculars or a 

low-power telescope will enhance the color, astronomers advise. 

Otherwise, warm clothing and perhaps a lounge chair and a hot beverage 

are all that's needed to enjoy the show.



"Unlike solar eclipses, lunar eclipses are completely safe to watch," 

said Fred Espenak, a veteran eclipse forecaster at NASA.



People in parts of western Asia will glimpse a bit of the eclipse, and 

it will be visible from all of Canada and Central and South America. 

People in the western United States will miss the earliest stages, when 

the Moon is in the penumbral shadow of Earth.



"But this is the least interesting and [least] dramatic part of the 

eclipse," Espenak said. "The more important and photogenic partial and 

total phases will be visible from all of North America with the 

exception of Alaska."



________________

Maury maurysis@ev1.net





************************************************************************

You are currently subscribed to the Radsafe mailing list. To

unsubscribe, send an e-mail to Majordomo@list.vanderbilt.edu  Put the

text "unsubscribe radsafe" (no quote marks) in the body of the e-mail,

with no subject line. You can view the Radsafe archives at

http://www.vanderbilt.edu/radsafe/