Wednesday, May 14, 2003

Lunar eclipse: May 15 / 16



The first eclipse of 2003 occurs on the evening of Thursday, May 15 (in Europe, the eclipse occurs during the early morning hours of Friday, May 16). This event is a total eclipse of the Moon which will be visible from North and South America as well as Europe, Africa and Antarctica. During such an eclipse, the Moon's disk can take on a dramatically colorful appearance from bright orange to blood red to dark brown and (rarely) very dark gray.

What is an eclipse of the moon? Introduction to Astronomy: The Motion of the Moon

What The Qur'an says about Moon: Do you realize that Qur'an was revealed between 610- 632 CE, and it contains facts discovered in the 20th century? Posted by Aladdin

Tomorrow, on the night of May 15, millions of eyes will be drawn skyward, where a mottled, coppery Moon will be immersed in the long, tapering cone of shadow cast by Earth. If the weather is clear, viewers across most of North America, all of South America, as well as Central and Western Europe and most of Africa (except the extreme eastern part), will witness a total lunar eclipse. This makes for a potential audience for the eclipse of approximately 2 billion people.

For North America, this will be the first total lunar eclipse in more than three years. The last such eclipse was seen on Earth was on Jan. 9, 2001, but mainly only in the Eastern Hemisphere. The last observable lunar eclipse visible in the Western Hemisphere happened on Jan. 20 and 21, 2000.

The May 15 event will begin when the Moon enters the faint penumbra (outer portion of Earth's shadow), about an hour before it begins moving into the umbra (Earth's black, inner shadow). The penumbral portion of the eclipse is invisible to the naked eye until the Moon becomes deeply immersed in it. Unaided observers should get their first glimpse of the penumbra on the left part of the Moon's disk at or around 9:46 p.m. Eastern Daylight Time (EDT) on May 15. The eclipse becomes more dramatic when the Moon begins to enter the Earth's umbra. A small sliver of darkness will begin to appear on the Moon's left edge at 10:03 p.m. EDT. The Moon will then take 3 hours and 14 minutes to pass completely through the umbra, and slightly less than one-third of that time it will be entirely immersed in shadow.

While much of the eastern and central portions of the U.S. and Canada will see the Moon entering the eclipse, those living to the west of a line running from near Tucson, Arizona to Minot, North Dakota and Port Nelson, Manitoba, will see the Moon rise already in eclipse. Because of low altitude and bright evening twilight, observers in these western locations may not see much of the Moon until it begins to emerge from the eclipse.

During the eclipse, although the Moon will be completely within Earth's shadow, it probably will not disappear from sight. It probably will appear to turn a copper, reddish hue. This coloring effect is due to Earth's atmosphere bending sunlight into the shadow. The Earth's shadow is cone-shaped and extends out into space for roughly 857,000 miles. Sunlight will be strained through a sort of double sunset all around the rim of the Earth, into its shadow and then onto the Moon.

Here are a few selected western cities in the U.S., and the moonrise and percentage of lunar diameter that will be seen inside Earth's shadow at moonrise. (All times given are local).

Phoenix, Arizona
7:12 p.m. 13%

Salt Lake City, Utah
8:28 p.m. 35%

Las Vegas, Nevada
7:31 p.m. 39%

Los Angeles, Calif.
7:39 p.m. 51%

Helena, Montana
8:45 p.m. 59%

Boise, Idaho
8:54 p.m. 72%

San Francisco, Calif.
8:05 p.m. 87%

The Moon will be setting in total eclipse across portions of east-central Africa and central Europe. Because of low altitude and bright morning twilight, observers in those locations may not see much of the Moon after it slips completely into the Earth's shadow.

The Moon will pass entirely out of the Earth's shadow at 1:17 a.m. EDT, May 16, and the last evidence of the penumbra should vanish around 1:34 a.m. EDT on May 16.

The next total lunar eclipse visible from most of the Western Hemisphere, Europe, Africa and Asia, will be on Nov. 8th and 9th, 2003.

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