Firearm & Gun Forum - FireArmsTalk.com

Firearm & Gun Forum - FireArmsTalk.com (http://www.firearmstalk.com/forums/)
-   The Club House (http://www.firearmstalk.com/forums/f12/)
-   -   Lunar Eclipse (http://www.firearmstalk.com/forums/f12/lunar-eclipse-35821/)

doctherock 12-20-2010 05:08 AM

Lunar Eclipse
 
For a few hours on the night of Dec. 20 to Dec. 21, the attention of tens of millions of people will be drawn skyward, where the mottled, coppery globe of our moon will hang completely immersed in the long, tapering cone of shadow cast out into space by our Earth. If the weather is clear, favorably placed skywatchers will have a view of one of nature's most beautiful spectacles: a total eclipse of the moon.

[Manmade wonders: Local guides to the best Christmas lights near you]

Unlike a total eclipse of the sun, which is only visible to those in the path of totality, eclipses of the moon can usually be observed from one's own backyard. The passage of the moon through the Earth's shadow is equally visible from all places within the hemisphere where the moon is above the horizon.

The total phase of the upcoming event will be visible across all of North and South America, as well as the northern and western part of Europe, and a small part of northeast Asia, including Korea and much of Japan. Totality will also be visible in its entirety from the North Island of New Zealand and Hawaii a potential viewing audience of about 1.5 billion people. This will be the first opportunity from any place on earth to see the moon undergo a total eclipse in 34 months. [Amazing photos of a total lunar eclipse]

This star chart shows where in the sky the upcoming lunar eclipse will appear. And check this NASA lunar eclipse chart to see how visible the eclipse will be from different regions around the world.

Stages of the eclipse

There is nothing complicated about viewing this celestial spectacle. Unlike an eclipse of the sun, which necessitates special viewing precautions in order to avoid eye damage, an eclipse of the moon is perfectly safe to watch. All you'll need to watch are your eyes, but binoculars or a telescope will give a much nicer view.

The eclipse will actually begin when the moon enters the faint outer portion, or penumbra, of the Earth's shadow a little over an hour before it begins moving into the umbra. The penumbra, however, is all but invisible to the eye until the moon becomes deeply immersed in it. Sharp-eyed viewers may get their first glimpse of the penumbra as a faint smudge on the left part of the moon's disk at or around 6:15 UT (on Dec. 21) which corresponds to 1:15 a.m. Eastern Time or 10:15 p.m. Pacific Time (on Dec. 20).

The most noticeable part of this eclipse will come when the moon begins to enter the Earth's dark inner shadow (called the umbra). A small scallop of darkness will begin to appear on the moon's left edge at 6:33 UT (on Dec. 21) corresponding to 1:33 a.m. EST or 10:33 p.m. PST (on Dec. 20).

The moon is expected to take 3 hours and 28 minutes to pass completely through the umbra.

The total phase of the eclipse will last 72 minutes beginning at 7:41 UT (on Dec. 21), corresponding to 2:41 a.m. EST or 11:41 p.m. PST (on Dec. 20).

At the moment of mid-totality (8:17 UT/3:17 a.m. EST/12:17 a.m. PST), the moon will stand directly overhead from a point in the North Pacific Ocean about 800 miles (1,300 km) west of La Paz, Mexico.

The moon will pass entirely out of the Earth's umbra at 10:01 UT/5:01 a.m. EST/2:01 a.m. PST and the last evidence of the penumbra should vanish about 15 or 20 minutes later.

Color and brightness in question

During totality, although the moon will be entirely immersed in the Earth's shadow, it likely will not disappear from sight. Rather, it should appear to turn a coppery red color, a change caused by the Earth's atmosphere bending or refracting sunlight into the shadow.

Since the Earth's shadow is cone-shaped and extends out into space for about 844,000 miles (1,358,000 km), 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.

However, because of the recent eruptions of the Eyjafjallaj�kull volcano last spring and the Merapi volcano in Indonesia in October, one and possibly even two clouds of ash and dust might be floating high above the Earth. As a result, the moon may appear darker than usual during this eclipse; during totality, parts of the moon might even become black and invisible.

A careful description of the colors seen on the totally eclipsed moon and their changes is valuable. The hues depend on the optical equipment used, usually appearing more vivid with the naked eye than in telescopes. The French astronomer Andre-Louis Danjon introduced the following five-point scale of lunar luminosity ("L") to classify eclipses:

L = 0: Very dark eclipse, moon almost invisible, especially in mid-totality.

L = 1: Dark eclipse, gray or brownish coloration, details distinguishable only with difficulty.

L = 2: Deep red or rust-colored eclipse, with a very dark central part in the shadow, and outer edge of the umbra relatively bright.

L = 3: Brick red eclipse, usually with a bright or yellow rim to the shadow.

L = 4: Very bright copper-red or orange eclipse, with a bluish very bright shadow rim.

Examine the moon at mid-totality and also near the beginning and end of totality to get an impression of both the inner and outer umbra. In noting an L observation, state the time and optical means (naked eye, binoculars or telescope) that is used. We invite readers to e-mail their Danjon estimate for this eclipse (along with any pictures they'd like to share) to cmoskowitz-at-SPACE.com.

At mid-totality, from rural locations far from city lights, the darkness of the sky is impressive. Faint stars and the Milky Way will appear, and the surrounding landscape will take on a somber hue. As totality ends, the eastern edge of the moon begins to emerge from the umbra, and the sequence of events repeats in reverse order until the spectacle is over.

Fringe effects

Interestingly, from most of New Zealand, a slice of northeast Australia, Papua, New Guinea, southwest Japan and Korea, the moon will rise during totality on the evening of Dec. 21. Because of low altitude and bright evening twilight, observers in these locations may not see much of the moon at all until it begins to emerge from out of the Earth's shadow.

Conversely, much of the United Kingdom and parts of western and northern Europe will see the moon set during totality on the morning of Dec. 21. Because of low altitude and bright morning twilight, observers in these locations may not see much of the moon at all after it slips completely into the Earth's shadow.

Past and future

The last total lunar eclipse occurred on Feb. 20 to Feb. 21, 2008 and was visible from most of the Americas, as well as Europe, much of Africa and western Asia. In 2011, there will be two total lunar eclipses. The first, on June 15, will be visible primarily from the Eastern Hemisphere and will have an unusually long duration of totality lasting one hour and 40 minutes.

winds-of-change 12-20-2010 07:35 AM

I'm looking forward to this. I will be working that night and I'll go to the top floor of the hospital to try to see the eclipse but I'm afraid we are expected to have a heavy cloud cover.

Shihan 12-20-2010 02:47 PM

What will Werewolves do?

notdku 12-20-2010 07:18 PM

Quote:

Originally Posted by Shihan (Post 406322)
What will Werewolves do?

Watch the eclipse.

doctherock 12-20-2010 07:23 PM

On a side note smartass, Shihan, This is the first time in 400 years that two celestial events take placve at the same time. The winter equinox and a lunar eclipse.

Shihan on a side note I stood up for you today. Someone said "you eat sh!t sandwhiches and howl at the moon. "
I stepped in and said " whoa hold on now, I happen to know that shihan doesnt like bread."

bkt 12-20-2010 07:39 PM

You're saying I should get up at 2:30AM and go out and stand in the snow and watch this?

Sounds good to me. I'll do it.

Shihan 12-20-2010 09:45 PM

Quote:

Originally Posted by doctherock (Post 406412)
On a side note smartass, Shihan, This is the first time in 400 years that two celestial events take placve at the same time. The winter equinox and a lunar eclipse.

Shihan on a side note I stood up for you today. Someone said "you eat sh!t sandwhiches and howl at the moon. "
I stepped in and said " whoa hold on now, I happen to know that shihan doesnt like bread."

We did a special on werewolves in High School.:D

doctherock 12-20-2010 10:20 PM

Quote:

Originally Posted by Shihan (Post 406502)
We did a special on werewolves in High School.:D
YouTube - Special Poetry Slam - Werewolf

I notice the resemblence, you are the guy in the fron wheel chair right shihan? LOL

doctherock 12-20-2010 10:21 PM

Quote:

Originally Posted by bkt (Post 406424)
You're saying I should get up at 2:30AM and go out and stand in the snow and watch this?

Sounds good to me. I'll do it.

As always it will be raining and stormy here so I wont get to marvel at it.

c3shooter 12-20-2010 11:49 PM

Cold, clear, not a cloud in the sky- perfect viewing weather. I will set the alarm clock and leave the blinds open so I can peek out the window. Gonna be too damned cold! Usually get interesting colors- kind of a coppery red. Hm- come to think of it, I DID get that 60X spotting scope this summer.......


All times are GMT. The time now is 09:20 AM.

Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.