Talk:Lunar eclipse

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[edit] Lunar Eclipse Diagram

The latest lunar eclpise happened at 9:43 February 20th 2008 seen in Canada. I removed "[[Image:Lunar eclipse diagram-en.svg|280px|thumb|" from the article, as it shows the sun somehow revolving around the earth. As far as i know, this is incorrect. PCRRN (talk) 01:09, 27 December 2007 (UTC)

Sorry for the confusion, but it isn't incorrect from an observational point of view. From the perspective of a viewer on earth, the sun's direction relative to the fixed stars travels around the ecliptic in one year, and the direction of the moon travels around the ecliptic in one month. I restored the image. Tom Ruen (talk) 01:23, 27 December 2007 (UTC)
Can you make that clear on the image then? PCRRN (talk) 23:11, 27 December 2007 (UTC)
I can't change the image myself, but I changed the caption. I'm not sure what I'd change on the diagram itself - it shows the earth in the center. I guess it would help to show the 12 zodiac names around in a circle, to help imply its a fixed-star reference frame. Tom Ruen (talk) 23:28, 27 December 2007 (UTC)

Ok, thanks for changing it. PCRRN (talk) 16:34, 29 December 2007 (UTC)

There is also something wrong in the caption, something inconsistent. Is the perceived circle a year in duration? A month? Both? The caption text says "As seen by an observer on earth, the Moon crosses the ecliptic every orbit at positions called nodes twice every month. When the full moon occurs in the same position at the node, a lunar eclipse can occur. These two nodes allow two eclipses per year, separated by approximately six months." Well, if the moon crosses the ecliptic twice a month, then where does the "allow two eclipses per year" part come in?? Ronewolf (talk) 18:15, 21 February 2008 (UTC)

Oh perhaps it gets hard to explain clearly. An eclipse can only occur at two points in the moon's orbit, called the nodes, where it crosses the path of the sun. A lunar eclipse occurs when the sun is opposite the moon when its crossing the nodes. Currently this can happen in February and August. Tom Ruen (talk) 18:40, 21 February 2008 (UTC)

[edit] Earthlight

The text under the first photograph claims that at a full lunar eclipse the moon is lit only by "Earthlight." Surely, as it says in the rest of the article, the moon is actually lit by the refracted sunlight curving around the Earth?
On that note, would it be good to point out that the reason the moon's color is most commonly reddish is because of this refraction, making it similar to a red sunset?
Asbestos 29 Oct 2004.


[edit] 4 May 2004 eclipse

Does anyone know what time the eclipse on the 4th of May is due to happen in the various locations across the region it will affect? A URL would be sufficient; I'll tabulate and add the information here, copyright permitting. Mr. Jones 08:48, 1 May 2004 (UTC)

http://sunearth.gsfc.nasa.gov/eclipse/LEplot/LEplot2001/LE2004May04T.gif

hi stu

[edit] Lunar Eclipse of Piye

Pharaoh Piye from 752-721 BC, a Kushite pharaoh, travelled North to the Nile Delta, for a year, then returned South to Kush and inscribed his "Piankhi Stela" (an autobiography). The famous, 1906, Breasted five-volume work, Ancient Records of Egypt,1907, has the translation, and it takes up some 40 pages. This autobiography on a stela mentions a night-time lunar eclipse (and the implications to his military/pharaonic activities). Maybe someone could research it, and find out what time of which year (season) the eclipse may have occurred? Michael McAnnis, be 732 BC. Thus, the eclipse occurred prior to 732. Breasted's translation is still probably the best source of information, that I know of? Any takers for figuring out the time of the eclipse?...good luck, and enjoy...MichaelMcAnnis,ArizonaUSA....Mmcannis 03:57, 30 October 2005 (UTC)

[edit] Difference between New Moon and Total Lunar Eclipse?

Isn't the monthly new moon a lunar eclipse (i.e. the moon passing into the earth's shadow)? What is the difference with the harvest moon, which turns a reddy-brown colour?

The monthly new moon is when the moon's shadow faces us, ie, the sunlit bit is facing away from us. This is why Solar Eclipses occur at new moons - the moon is between the Earth and the Sun - and why lunar eclipses happen at full moons - the Earth is between the Moon and the Sun. The moon's orbit is inclined to the Earth's by about five degrees, and is slightly eliptical, as is the Earth's orbit about the Sun, which is why not every new moon is accompanied by an eclipse, and similarly for full moons. Normal harvest moons are just very bright full moons close to the autumnal equinox, more notable for their size than their colour. They tend to be very bright yellow, but if eclipsed, then it can go reddy-brown. MilleauRekiir 18:48, 6 September 2006 (UTC)


Nope, not even size or color but the uninteruptability of light to work by. Harvest moons are the ones that rise at dusk almost the same time each night for several nights so the harvesting doesn't have to stop. Sagittarian Milky Way 07:30, 2 March 2007 (UTC)

[edit] Re:Difference between New Moon and Total Lunar Eclipse?

No, the new moon is not a total lunar eclipse as it is not in the earth's shadow. The new moon is unilluminated because the side of it has turned away from sunlight(due to the moon's rotation),hence the phrase,The dark side of the moon.


"The Lunar Eclipes is not a shadow. Its one of the most things you may ever see. If you really take the time and look at the sun or the moon.....it has more than 1 features then youll ever think. Shadows dose not have nothing to do with the Lunar Eclipes. Make sure that you know what you are talking about......therefore...I am good at that stuff. Its called Paying Attintion in school And studying about stuff. thanks for you time....."

                       Mallory S.       May 14, 2006 
                                            11:48pm

[edit] Total lunar eclipses set to end?

I remember reading a long time ago that total lunar eclipses would not occur after a certain point in time due to the moon gradually moving further away from the earth? Brianjd


I think you are probably referring to total solar eclipses not happening after a certain period of time (again, due to the moon moving father from the earth as a result of the tides on earth and the conservation of angular momentum) - but there's about 600 million years before tidal acceleration finally results in the last total solar eclipse. It may not happen for lunar eclipses - it depends on what the final earth-moon distance is when it gets to a tidally locked orbit, and whether the sun has destroyed the earth-moon system beforehand... Coatesg 16:51, 8 June 2007 (UTC)

[edit] European eclipse list

This list is only half translated from German, only applicable to Europe. and rather unsightly. I will remove it, if nobody gives a good reason to keep it, eg. by improving it drastically. Awolf002 30 June 2005 22:13 (UTC)


[edit] Vandalism

Beware of vandalism reading, "The moon is made of cheese!" I have removed this.

No need to comment on reverting vandalism. This page gets lots of silly edits, and anyone can fix it by reverting to a previous version. Thanks! Tom Ruen 07:12, 8 May 2006 (UTC)

[edit] Top diagram

The moon looks weird like that. It should be more or less circular. Does anyone know how to fix it?--Shantavira 13:34, 8 September 2006 (UTC)

[edit] Suggestions for improvement before nominating as a Good article

I have a few comments that might be useful for improving this article.

  • I don't think that the first image should be in the introducing paragraph. Also the first image is not as good as the ones found on the solar eclipse page. For instance, the umbra and penumbra should be labeled, and the straight lines for "sun light" is somewhat of a misrepresentation.
  • The second figure needs information in the caption. When I first looked at this, I thought "are you sure this is a lunar eclipse, and not just a phase of the Moon?"
  • It is not clear if the paragraph starting with "Because the Moon's orbit around the Earth is inclined 5° with respect to..." should be in the section "Types of lunar eclipses". I would probably place all the material that follows this in a section that describes the orbit of the Moon and its relationship to eclipses.
  • "If you were on the Moon's surface during a lunar eclipse you would witness a solar eclipse, " I presume that it would be a "total" solar eclipse, as opposed to annular. You could also mention that the temperature at the lunar surface was measured during lunar eclipses as part of the ALSEP heat flow experiment.
  • Perhaps a short table noting when future lunar eclipses will occur should be added here.
  • Concerning the section "Longest total lunar eclipse between 1900 and 2000", it should be noted that there is a maximum duration that a lunar eclipse can be that is a function of its orbit geometry.
  • History "Indian mathematician Aryabhata gave accurate calculations for both the solar eclipse and lunar eclipse." They gave calculation of what? predictions of when they will occurr? length?
  • Is this really necessary? "The total eclipse on October 27, 2004 occurred during game 4 of MLB's World Series" I presume that there are much more interesting historical eclipses.

Lunokhod 14:18, 24 November 2006 (UTC)

[edit] Duration of Eclipse at Apogee

The text explaining why a lunar eclipse can be longer at apogee could use clarification on the following point: "Specifically, a totally-eclipsed Moon being concomitantly at or near apogee will lengthen the duration of totality for two reasons: first, the Moon will appear to move more slowly across the umbra, and second, the Moon will appear smaller as seen from Earth and therefore remain inside the umbra longer." -- A curious reader (me) will wonder whether or not this is actually the case, given that while the moon appears smaller, the umbral cone is also smaller at apogee. Does one of these differences dominate the other, and why? Either an explanation or a citation would be beneficial. 136.159.119.31 19:34, 3 January 2007 (UTC)

The umbral cone has a top angle equal to the parallax of the Sun: only 8.8". So iys diameter differs only very little at the location of the apogee and the perigee. I'll add this to the text. Tom Peters 10:33, 12 January 2007 (UTC)

[edit] Is "Longest total lunar eclipses between 1900 and 2100" necessary?

Does anyone else find that the section "Longest total lunar eclipses between 1900 and 2100" is not terribly useful? The durations only differ by about 7 minutes, and given that the eclipses are almost 2 hours in duration, an observer without a clock is not going to notice this. Perhap we can summarize this section in one or two sentences by just saying that eclipse durations can last up to X minutes. In fact, there is probably a maximum upper limit that can be stated. Lunokhod 19:58, 3 January 2007 (UTC)

agreed WizardFusion 10:07, 12 January 2007 (UTC)

[edit] wow

the sun is directly at earth during a lunar eclipse! it must be VERY hot in those places! the moon looks cool when its orange! wow!

[edit] Vandalism

I am sorry, but I cannot stop whoever is vandalizing this page. This is a public IP address, and hundreds have access to this page every day. 169.204.137.5 21:56, 6 February 2007 (UTC)

[edit] Got TWO

Got one in March 3, 2007, and another one in August, 2007. Go to www.almanac.com/Eclipses for more.205.240.146.224 08:49, 26 February 2007 (UTC)

These will, for some areas, will be selenelion/selenehelion in some areas of the US. See above website for more info. 205.240.146.224 08:58, 26 February 2007 (UTC)

[edit] Lunar eclipse

A lunar eclipse is where the sun, moon & earth line up and the lunar surface dissapers totally this is called an allignment which happens every 5,000 years we are lucky to experiance this tonight —The preceding unsigned comment was added by Enchantian2 (talk • contribs) 10:13, 3 March 2007 (UTC).

A baby is where the mummy & daddy line up and the clothes dissapers totally this is called an session which happens every 5,000 minutes we are lucky to experiance this at all with our level of intelligence —The preceding unsigned comment was added by 85.210.176.24 (talk) 23:19, 3 March 2007 (UTC).

[edit] March, 2007 lunar eclipse

I think the photo http://en.wikipedia.org/wiki/Image:LunarEclipse0303072244.jpg should be at the top. --jazzle 00:08, 4 March 2007 (UTC)

I really think it should be at the top too. But images have been removed unless there are some of you who agrees with Jazzle. --Dat789Dat789 12:31, 6 March 2007 (UTC)

Actually in Northern England its fully visible. OsirisV 22:03 3/3/07

From New England. The moon is not yet visible. Current time 6:27PM.

in the 'description' section, it says lunar eclipses occur every two years, and further down it says they occur at least twice a year.

Please can we not have 15 pages of identical (bad) photos of the 3 March eclipse... makes the article very untidy :( —The preceding unsigned comment was added by 82.26.181.238 (talk) 01:13, 4 March 2007 (UTC).

How do you get rid off all that white space near the top of the page?--88.104.122.144 12:40, 4 March 2007 (UTC)

I don't thing that this was the first ever total lunar eclipse - could be made clearer Martinmarv (talk) 20:17, 21 February 2008 (UTC)

[edit] Better photos for the 3 March eclypse

I second the previous comment, the quality of the current photos is very poor. There are plenty of CC-licensed photos of excellent quality available at high resolution on Flickr. You may also want to take a look at the following groups:

--DarTar 10:43, 4 March 2007 (UTC)

We also need to get rid of some of the pictures currently in the article. There are so many at the moment that the article has become a mess. ··· rWd · Talk ··· 09:42, 5 March 2007 (UTC)
rWd, see also my comment here --DarTar 10:04, 5 March 2007 (UTC)
I went ahead and removed some of the March 3/4 images. The article still needs some more work, because it's still too cluttered and messy, imo. This includes the 'Description' section, which looks bad now with images both on the left and right side of the text. ··· rWd · Talk ··· 09:42, 6 March 2007 (UTC)
Some of the removed images should be preserved under the heading "Recent Images of the eclipse" or something akin to that. -Dat789 12:28, 6 March 2007 (UTC)
I disagree. This is an encyclopedia, not an image gallery. The article now has three pictures of actual lunar eclipses and that should suffice. If people want more, they can go to Flickr. ··· rWd · Talk ··· 14:15, 8 March 2007 (UTC)
Wikipedia is not an image gallery per se but it does not breach Wikipedia's policies to have a few more images on the article. However, you're right, people can go to places like Flickr or the like for more images. Perhaps because there are only a limited variations of the moon's image.-Dat789

[edit] Two conditions??

Surely there is only one condition for a lunar eclipse to occur. Sun, Earth and Moon in alignment. The Moon is bound to be full under such an alignment and therefore cannot be a condition for an eclipse to occur. It would be OK to say that a lunar eclipse can only occur during a full moon, but it cannot be a condition. —The preceding unsigned comment was added by 195.195.173.199 (talk) 11:29, 6 March 2007 (UTC).

Be careful about saying all you need is alignment - they can be all lined up nicely at new moon too, though that will never lead to a lunar eclipse - but you might get a solar eclipse instead. So I'd say full moon was the better condition, as it's more specific than "alignment". Since full moon doesn't always lead to an eclipse, that's where the second condition comes in. It could probably be phrased better in the article though. Spiral Wave 18:01, 7 March 2007 (UTC)
Like this? "[A lunar eclipse] can occur only when the Sun, Earth and Moon are aligned exactly, or very closely so, with the Earth in the middle. Hence, the Moon is always full during a lunar eclipse." The only requirement for an eclipse is alignment (or near-alignment) of these three bodies with the Earth between the other two. The full Moon is itself not a requirement--it's a consequence of the required alignment. ··· rWd · Talk ··· 14:25, 8 March 2007 (UTC)
Yeah, I see the change you've made - reads well - but I was under the impression the above comment was about the "two conditions" given in the opening paragraph of the Description section. There, the rotational and precessional motion has been decomposed, so the text is saying it has to be both at the right place in it's orbit, and passing through the ecliptic. To be honest, I think it's the phrasing - as two "conditions" - that's causing the problems. If it was simply stated that the Moon had to be near full/aligned behind the Earth, and passing though one of the two nodes, that would suffice. Saying that one of the nodes coincides with a full Moon is a single equivalent "condition"; hence the ambiguity. I think the best option is to remove all mention of "conditions" and simply explain what's physically happening. I'd do it but I'm so knackered I'd bork it right now. Spiral Wave 02:34, 9 March 2007 (UTC)
Changed the part I was refering to now. Hope this is acceptable.
Looks good. I totally overlooked this bit in the Description section. Thanks for taking care of that. ··· rWd · Talk ··· 14:49, 9 March 2007 (UTC)
Yup, that's much better. Good jobs all round. Spiral Wave 18:51, 9 March 2007 (UTC)

[edit] List of lunar eclipses

I began work on a list of lunar eclipses, using the same format as the list of solar eclipses. So far it only contains the two 2007 eclipses, but there are 228 more this century and there are another 230 from the 20th century that we may want to include. Please place further discussion on the article's talk page. ··· rWd · Talk ··· 08:21, 10 March 2007 (UTC)

[edit] Page Reverted due to poor edits

The article has undergone numerous changes in the last few weeks, and none appear for the better. I've reverted it to a previous version that seemed more substantial, grammatically correct, and informative. I'm unsure if useful edits were made in the last few weeks, it was hard to see through the changes for the worse which were made. At the least it is better to work from the reverted entry instead of the wholesale changes that had been made from what appeared to be inexperienced users.

[edit] Merge with Red Moon

Because of the simularities of the red moon and lunar eclipse page, plus the limited information on the Red moon page, I propose merging the two pages Iciac 08:33, 25 August 2007 (UTC)

[edit] July 2007 eclipse image

I've taken a photo of the 2007 eclipse: [1] I give permission for the image to be used in the article, or elsewhere in Wikipedia. I'd add it myself, but I have no idea how.  :P--Tiberius47 11:25, 28 August 2007 (UTC)

[edit] Why is there no "path of totality" for a lunar eclipse?

For solar eclipses, it is well known that there is a relatively narrow path of totality, outside of which the eclipse either appears as partial, or cannot be viewed at all. This is not true for lunar eclipses: everyone on the night side of Earth sees very nearly the same eclipse.

I believe this is because a "solar eclipse" is really an occultation of the sun by the moon. There is an observational difference between being in the shadow of something and casting a shadow on something. But I don't think the consequences of this difference are obvious to a layperson. Another way to think about it: from the moon's point of view, all "eclipses of the earth" (which we earthlings call solar eclipses) are penumbral, because the diameter of the moon's umbra is so much smaller than the earth's diameter.

It may be possible to make other interesting comparisons between solar and lunar eclipses.

Thanks,

Dynamitecow 23:30, 30 August 2007 (UTC)

[edit] I have a Question

Can there ever be a annular lunar eclipse? I'm curious. —Preceding unsigned comment added by 75.72.205.202 (talk) 04:40, 31 December 2007 (UTC)

No, not with the moon's current distance, and the earth's diameter. The earth's angular size viewed from the moon is about 1.8 degrees, while the sun is about 0.5 degrees. So if the moon was over 3 times further away (or the earth 1/3 as big), it could happen then. Tom Ruen (talk) 07:08, 31 December 2007 (UTC)

[edit] Why don't you see red until the moon is mostly eclipsed?

I would expect the encroaching dark part to be red too. Is it really red but somehow "washed out" for the camera by the non eclipsed white? What am I missing? This page is wonderful. Kendroberts (talk) 17:52, 31 December 2007 (UTC)

It's too bright. Sagittarian Milky Way (talk) 12:17, 5 February 2008 (UTC)

[edit] Ustream reference inappropriate

The reference for today's eclipse to ustream is inappropriate. Ustream is not notable.67.170.234.221 (talk) 03:30, 21 February 2008 (UTC)

[edit] Feb 20, 2008 Eclipse Visibility

The article falsely claims the eclipse was visible from Australia. This is NOT true as clearly explained by http://sunearth.gsfc.nasa.gov/eclipse/LEmono/TLE2008Feb21/TLE2008Feb21.html --Slashmasterc (talk) 13:49, 21 February 2008 (UTC)

Fixed, strange. I couldn't tell if error was vandalism or loopy thinking, was correct on the article page! Tom Ruen (talk) 17:29, 21 February 2008 (UTC)

[edit] Time sensitivity

I'm concerned that the section "Recent lunar eclipse events" is too time-sensitive, particularly the parts referring to "the next" lunar eclipse. Ref Wikipedia:Words_to_avoid#Words_whose_meaning_may_degrade_with_time. These wouldn't make sense in a print version of Wikipedia. I'm not sure what the best way to deal with this - one strategy is to have a table of lunar eclipses, together with a note that "This table was generated on <date>. Eclipses following this date are predicted and may change." Dcoetzee 23:07, 21 February 2008 (UTC)

[edit] The timelapse

I really like that timelapse video on here--Charlieh7337 (talk) 02:18, 22 February 2008 (UTC)

ugh ugh ugh ugh the moon is boring —Preceding unsigned comment added by 70.190.244.40 (talk) 22:48, 25 February 2008 (UTC)


[edit] Eclipse color image

This image and text was in the gallery:

The Sun's light color within the Earth's shadow.

Can anyone confirm the correctness of this symbolic representation of the sunlight? I thought it was due to the blue light being scattered more than a refractive difference. Obviously the light inside the umbral shadow is all due to refraction through the atmosphere, but more than that I can't say. So feel free to move it back if anyone can defend it. It is pretty - deserves to be in a larger image connected to the text with a better description, again if true. Tom Ruen (talk) 06:57, 1 March 2008 (UTC)

[edit] Misleading diagram

The diagram that leads off this article is quite misleading as the sun's rays are essentially parallel given the relative distances. (Discuss here or at the diagram's talk page.) Hgilbert (talk) 14:41, 16 March 2008 (UTC)

[edit] Lunar eclipse photo gallery

http://commons.wikimedia.org/wiki/Category:Lunar_eclipse SockPuppetForTomruen (talk) 21:10, 22 March 2008 (UTC)