Talk:Solar eclipse

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Gravity anomalies[edit]

The following text included in the "Gravity anomalies" section is a fragment:

"In 1954 and again in 1959, Maurice Allais reported that his observations of the strange/unexplained movement during solar eclipses."

I don't know what the intended meaning was to be, so I'm not changing it, but perhaps someone can complete the thought? Moonharpoon (talk) 05:25, 4 April 2010 (UTC)

Rarity[edit]

The article says, "Solar eclipses are an extreme rarity within the universe at large." Well, in our Solar System, they're very rare to unique, depending on how one defines things. One might have them on Mars or Pluto, but the match between the apparent size of our Moon and the Sun as seen from Earth is unique (Mars can never have better than an annular eclipse, and on Pluto, the moons are seen much larger than the Sun). But to say they are rare in the universe at large is, I think, a bit of a stretch. We really don't know, and the best we could say is, they are PROBABLY rare. Odds are that the circumstances wouldn't happen very often, but those odds would increase if it turns out that a lot of planets have a lot of moons. I suppose there's also the (incredibly unlikely) possibility of on planet in a system casting an eclipse on another planet. 140.147.236.194 (talk) 21:04, 30 November 2010 (UTC)Stephen Kosciesza

Map interpretation/Legend[edit]

I'm an educated, curious layperson, and am frustrated by the fact that none, NONE of the maps (like the ones in section "occurrence and cycles") have a legend. All the lines are color coded, and nowhere can I find what those codes mean. A graphic with color coded (or using different line types) is close to useless without a LEGEND! This problem exists with ALL solar eclipse maps on wikipedia.

Can someone help us? 184.57.7.58 (talk) 00:28, 10 June 2011 (UTC)

Maps like File:SE1935Dec25A.png? Agreed there ought to be a legend. They are copied from Nasa charts, but were cropped. Ideally legend information ought to go in the file information, could be done with a template, and then referencing in each file variation. Tom Ruen (talk) 00:47, 10 June 2011 (UTC)
Do you know what the magenta lines refer to? Haven't been able to quite figure those out. P1 and P4, don't know why I never noticed that before. TimL (talk) 02:26, 10 June 2011 (UTC)
If you are referring to the file Tom links to. The legend is built into the diagram. The cyan lines refer to how much of the sun is eclipsed, (0.40 = 40%), the green lines refer to time of maximum eclipse over a given location, the magenta lines, if I'm not mistaken, represent point of first contact (P1) and point of last contact (P4) and are meant to show what will be visible when the eclipse is near sunrise or sunset. The middle magenta line represents either sunrise or sunset. Subsolar refers to the location where the sun is directly overhead during greatest eclipse. TimL (talk) 02:46, 10 June 2011 (UTC)
Here's the original [1] Tom Ruen (talk) 02:48, 10 June 2011 (UTC)

Reduce time span of "Total Solar Eclipse Paths: 1001–2000" image?[edit]

Total Solar Eclipse Paths: 1001–2000. This image was merged from 50 separate images from NASA.[1]

I find that the image "Total Solar Eclipse Paths: 1001–2000" in Solar_eclipse#Occurrence_and_cycles (reproduced on the right) covers way too long a time span and hence does not provide much useful information, other than where eclipses have not occurred.

A span of 20 years, such as 2001–2020 paths or a composite of, say, 100 years centred on approximately the current year (1961–2060) from images on NASA to World Atlas of Solar Eclipse Paths may be more readable.

No doubt User:Yaohua2000 has put in a lot of effort to composite the NASA images, so before I change the image, what do you think?

Thanks, cmɢʟeeτaʟκ 11:50, 13 June 2011 (UTC)

First as a seasoned Wikipedian you ought to know that new comments go on the bottom. Second the point of the image is to show the nearly complete coverage of the earth by total eclipses over a long time span, I've clarified this in the image caption. Please do not modify the image. It is not meant to show the paths of individual eclipses. Thank you. TimL • talk 17:52, 13 June 2011 (UTC)
The end of the article list upcoming solar eclipses, I placed your suggested image there. Seemed relevant to me. TimL • talk 18:14, 13 June 2011 (UTC)
Point taken, thanks. cmɢʟeeτaʟκ 11:54, 30 June 2011 (UTC)

A really nice and useful addition would be a picture of an eclipse from space[edit]

A picture of the surface of the earth during an eclipse can be very helpful in so much of this explanation. You can see the darkest center where it is total and the lighter shadow around it etc. A good example is on the nasa site at http://apod.nasa.gov/apod/ap990830.html" - not sure if that is considered public domain or not. — Preceding unsigned comment added by 69.119.112.149 (talk) 04:26, 26 August 2011 (UTC)

Good idea, but that image is copyright CNES. This one by NASA seems fine, but less useful: [2] (perhaps better losslessly rotated 180°). Others: [3] [4] cmɢʟeeτaʟκ 17:23, 26 August 2011 (UTC)
Eclipse fromISS 2006-03-29.jpg
Correction: There's already one in the Solar_eclipse#Artificial_satellites section, though I'd prefer [5] rotated 180°. cmɢʟeeτaʟκ 17:35, 26 August 2011 (UTC)

This animation is pretty nice: SockPuppetForTomruen (talk) 20:53, 26 August 2011 (UTC)

ECLIPS MSG VIS.GIF
  1. 6 (antarctica) is pretty visually striking. Not to mention quite illustrative (w/ good caption) IMO I like it. TimL • talk 20:43, 27 August 2011 (UTC)
────────────────────────────────────────────────────────────────────────────────────────────────────Also, looking in the other direction, there's The Apollo 12 view of a solar eclipse, about which see this and this (that last includes a link to a 47Mb TIFF, which appears to be a different image entirely). It is used on this NASA page. Here is a web page containing link to a playable movie of a solar eclipse as seen from Japan's SELENE (Kaguya) lunar orbiter. Wtmitchell (talk) (earlier Boracay Bill) 22:59, 27 August 2011 (UTC)
Those are not solar eclipses, not in the sense of this article anyways. This article is about the moon blocking the sun, not the earth blocking it, as is in the case of lunar or spacecraft eclipses by the earth. TimL • talk 14:31, 28 August 2011 (UTC)

Annular eclipse--not necessarily a ring[edit]

I do know first-hand that rarely, an annular eclipse might not actually form a solid, unbroken ring. If it is very near to total--that is, magnitude just shy of 1.000000, the moon almost covers the face of the sun--then one might see a ring of irregular bright beads. This is not the same as the diamond ring effect, just before and just after totality, but the principle is similar.

I saw the annular eclipse of May 30, 1984 in Atlanta, Georgia, USA. That was so close to total that I remember some speculation that it might have been briefly total at the peak eclipse point around Petersburg, Virginia (the entire area had rain that day, and nobody on the ground there saw anything). I used a small telescope to project an image of maybe four inches diameter on card.

At the instant that the last crescent of the sun disappeared, the image abruptly changed to those irregular beads. Unfortunately, that lasted maybe less than a second, and by the time I pressed the shutter on my camera, the image had already jumped to the opposite crescent.

I also remember hearing that the beads are explained by mountains and valleys on the limb of the moon as we see it: where the terrain is high, it blocks the sun; where it is low, the sun shines through. But I haven't got citations to back this up. 140.147.236.195 (talk) 22:10, 20 January 2012 (UTC)Stephen Kosciesza

A very rare eclipse indeed (probably why the fact you refer to is not mentioned in the article). The eclipse may have been total somewhere along it's length due to variations of earth elevation. An eclipse so close to 1 in magnitude means that totality is achieved just above the ground (perhaps a thousand feet or so?) The article does explain the reason for the beads. I would have been 9 when this occurred, what would have been a very impressive partial eclipse where I live but don't seem to remember it. We may have got a break from classes to go out and see it if I remember correctly. Thanks for sharing. TimL • talk 05:46, 21 January 2012 (UTC)
Well, it does explain Bailey's Beads, the phenomenon shortly before and shortly after totality, when they're see at the points of the crescent that is the exposed portion of the face of the sun. Those are little spots of light at the ends of the crescent. What I saw was more like a string of pearls, of widely differing sizes and irregular placement. The governing principle is the same, but what we see is quite different. And yes, I suppose every total eclipse would show something of Bailey's Beads. This would have to be an annular eclipse that's just on the verge of totality.
BTW, I seem to remember reading somewhere that another variable for totality or not is the size of the sun. And unlike the others, that one is hard to predict. We know the size of the moon; since it's a big rock, it's virtually unchanging. And we know the distance to the moon very precisely, especially since astronauts left those optical reflecting devices behind. But the pulsations of a huge ball of gas and plasma--that's quite different. 173.79.191.234 (talk) 20:40, 22 January 2012 (UTC)Stephen Kosciesza
Actually the size of the sun is also virtually unchanging. The sun doesn't pulsate (at least not on less than astronomical time scales), like you describe, the surface may be quite chaotic, but that's another matter. The article does mention the apparent size of the sun does change though. What also changes is the sun's atmosphere which makes the appearance of the corona hard to predict, this is all mentioned in the article. I don't think the article mentions the pearls you saw because it would be such a rare phenomenon not mentioned in any literature. But the annular eclipse you saw very nearly blocked out the entire disk I would imagine, so briefly causing the pearls you describe. Certainly the shortest (lowest magnitude) total eclipses and shortest (highest magnitude) annular eclipses will share some characteristics, since the apparent size of the sun and moon (and hence magnitude) are only very slightly different. Sounds you definitely saw a very rare phenomena! TimL • talk 14:24, 23 January 2012 (UTC)
In discussing this with you, and mulling it over, it's occurred to me that the same phenomenon must happen at points just before and just after the totality path in a hybrid eclipse. Just before it reaches magnitude 1.00000000..., it would be magnitude 0.99999...
I wish I could get that one over again, to snap that picture. I think I was trying to snap pictures as fast as I could, then, as the center of the eclipse approached. Unfortunately, I was using a film (obviously) camera--a 1950s vintage Contaflex IV, on which I had to turn a knob manually to wind the film. I think I was probably winding at those few moments with the pearl necklace. — Preceding unsigned comment added by 140.147.236.195 (talk) 18:49, 24 January 2012 (UTC)

Safety[edit]

Is smoked glass actually safe? It seems like there could be a very wide variation in the thickness of the soot and it could be easily scratched. Showing a little kid using it makes me cringe. That's just has to be a bad idea.

Those plastic eclipse glasses do not seem much better.

There is no discussion of either smoked glass or the eclise glasses in the text. — Preceding unsigned comment added by 67.170.137.158 (talk) 05:32, 5 June 2012 (UTC)

According to this article an the article already cited in the text, it is not safe. Removed image, referred to the danger of using smoked glass in text and added citation. TimL • talk 01:19, 8 November 2012 (UTC)

Final total eclipse[edit]

The reference provided at the end of this section didn't match the numbers in the article. Indeed, the rate of recession of the moon is about 3.8 cm/y, but the source gives 2.2. The distance the moon has to cover was also different, and chances are that the source is wrong on that front as well. However, until a proper source is found, I changed the numbers to the current ref's. I'd search myself, but I'm busy at the moment... EricLeb01 (Page | Talk) 21:54, 11 May 2013 (UTC)

Safety Issues: hype or fact?[edit]

The fact remains that many people, myself included, look at a direct full sun with no retinal impairment whatsoever. Indeed it seems highly improbable that our eyes would have evolved into such vulnerable organs of perception in a world where it would be quite natural to look inquisitively upon the source of heat, light, and even life itself. During the sixties, Life magazine (or it may have been Look) reported in a story on Pablo Picasso that the celebrated genius, who depended on his eyes as few men ever did, had a habit of staring for long periods directly into the blaze of a Spanish sun. Orthotox (talk) 07:08, 22 August 2013 (UTC)

Permanent eye damage is high price to pay for curiosity. There are apparently supporters of sungazing already explained there. What more do you want? Myself, I recognize the sun's brightness is very different from straight overhead to near the horizon, and humidity and smog can also dim the sun perhaps many orders of magnitude, but you also have to consider what part of the radiation is damaging, and whether visual pain is an accurate representation of the danger. Maybe we can get 100 monkeys and experiment on them on different conditions, or perhaps your friends would like to volunteer to help, so science can give detailed suggestions under what conditions we can safely stare at the sun? Tom Ruen (talk) 07:50, 22 August 2013 (UTC)
"The fact remains that many people, myself included, look at a direct full sun with no retinal impairment whatsoever." This is patently absurd/false. You might think you are looking directly at the sun when in fact you are actually only gazing very close to it. To stare directly at the sun would be excruciatingly painful, in fact it happens to me accidentally every so often and I can attest to the fact that it is very painful, not to mention if you really could stare directly at the sun, the projected image of the sun on your retina would be enough to severely burn it causing permanent damage. The eye has a autonomic reflex to look away from the sun if its gaze happens to catch it directly. TimL • talk 15:15, 22 August 2013 (UTC)
"The truth is, you can in fact look at the sun during the sunset and sunrise without too much trouble. It has been in practice to look at the sun in 6-second intervals during these times as a meditivatemeditative and medicinal practice, both respectively for praising the sun and gaining vitamin D."
— Preceding unsigned comment added by Warrensk (talkcontribs) 03:44 [2 edits between successive minute ticks], 13 October 2013

"Fixed frame of reference"[edit]

   I edited that phrase in 4th 'graph of the section, to make it lk to Inertial frame of reference (keeping the same text visible by piping). I'm not sure it's the ideal lk, but it takes a lot more sophistication to realize there can be more than one frame of reference than it does to count days and hours between risings of the full moon, and the self-starters deserve some path forward.
--Jerzyt 07:33, 5 November 2013 (UTC)

Table in "Geometry" section[edit]

   A colleague has correctly perceived that the last rows of the table show something valuable that the first rows cannot as conveniently show, but has arranged it to make what the first rows show clear at the cost of making what the last rows show obscure. I have changed "Rank in descending order" to "Ordered in decreasing apparent size" which is hopefully more intuitive: "Rank" is ambiguous as to what is descending and as to whether 1 is highest or lowest rank, but i assume "1 comes first (reflecting least decreased size)" requires less mental gymnastics.
   But i think what would best serve users is a sortable table: i know our tables support sorting by a column value to determine the order of rows (tho if supported, perhaps sorting by row value to determine the order of columns would server better here); while focusing on what are currently the rows from "Sun/Moon" down to "Angular diameter", the present ordering of columns is ideal. Letting the user reorder the columns so the adjacent disks were those closest in diameter, while focusing on the rows from "Angular diameter" down to "rank ..." (or "order ..."), would make their relationship much more clear (even if the big moon and big sun might still be too hard to rank by eye even when adjacent).
--Jerzyt 09:13, 5 November 2013 (UTC)

Semi-protected edit request on 13 January 2014[edit]

External Animation Video on Eclipse from SarvaShikshan

Ganeshwatve (talk) 05:40, 13 January 2014 (UTC)

Not done: please be more specific about what needs to be changed. Where should this go? --Anon126 (talk - contribs) 05:54, 13 January 2014 (UTC)

NASA's eclipse information is out-of-date[edit]

In regards to the 2017 solar eclipse, I found out last summer that the United States Naval Observatory (USNO) has the eclipse maximum centered near Carbondale Illinois http://aa.usno.navy.mil/data/docs/Eclipse2017.php . Their time is four seconds longer than what is reported at NASA.

A man in New Mexico, a Michael Zeiler, at http://eclipse-maps.com/Eclipse-Maps/Welcome.html has the eclipse centered near Goreville Illinois. Eclipse chasers respect Mr. Zeiler’s work in regards to his eclipse maps because they are highly accurate. He has the eclipse time one second longer that what is shown at NASA. (Zeiler's results and USNO are 19 miles apart.) Michael gave me this information last month. With all that in mind, Mr. Fred Espenak has the eclipse still centered near Hopkinsville Kentucky. I wrote to him last year asking him about the new findings pointing to southern Illinois. Mr. Espenak’s response was, “Yes, I agree.”

I am aware Mr. Espenak had retired in 2009. NASA now considers him a volunteer. Yet, his information is out-of-date on the NASA website. The last time he updated his data was back in 2007 (except for some minor issues currently). NASA has decided not to hire a successor (as far as I can tell).

All of these changes are because of the new findings about our moon’s topography derived from the Lunar Reconnaissance Orbiter (LRO) probe that was launched back in 2009. USNO and Mr. Zeiler have incorporated the LRO findings into their data and maps. Mr. Espenak has not.

Almost everyone uses the NASA solar eclipse site as their main source of information. However, the public needs to be made aware of southern Illinois as being the center of maximum duration in 2017 and not Hopkinsville. But how do you do that with the NASA website showing dated material and everybody using it as their primary source of information? Nobody knows it is out-of-date!

USNO told me that they do not use the GE terminology...they prefer maximum duration! (Does Mr. Espenak and the staff at USNO ever chat with each other about the discrepancies?) Mr. Espenak did say he needs to rewrite the definition for GE. The reluctance by nearly everyone to accept the new information about Illinois has been quite frustrating! I can’t do much until NASA expresses in some shape or form, on their eclipse website, that what is being portrayed is dated! firstmagnitude (Larry Koehn) — Preceding unsigned comment added by Firstmagnitude (talkcontribs) 21:32, 3 February 2014 (UTC)

"Houston, we have a problem!" Hopefully as the 2017 eclipse approaches there will be an increased interest in updating the data. In light of this information, I wonder what the length of the supposedly longest eclipse in millennia of July 16, 2186 is? Do the discrepancies accumulate over time or are they stay constant? If we are just talking about new data about the exact shape of the moon I am guessing the discrepancies would be constant. From what I've seen so far it appears eclipses are lasting slightly longer than previously predicted.  — TimL • talk 23:42, 3 February 2014 (UTC)

Solar eclipse in culture[edit]

The FA violates comprehensiveness parameter. There are many legends explaining solar eclipses in various cultures [6][7][8]. Also, there are many superstitions/rituals to be observed during an eclipse, which are not covered. --Redtigerxyz Talk 06:57, 24 July 2014 (UTC)

Semi-protected edit request on 13 September 2014[edit]

Original text: The orbital planes cross each year at a line of nodes resulting

Is "year" the right word? Isn't "other" the correct?

179.27.2.102 (talk) 00:24, 13 September 2014 (UTC)

Yes check.svg Done Cannolis (talk) 00:49, 13 September 2014 (UTC)