https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=162.158.234.58&feedformat=atomexplain xkcd - User contributions [en]2024-03-29T06:31:25ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=Talk:2040:_Sibling-in-Law&diff=162167Talk:2040: Sibling-in-Law2018-08-31T18:53:58Z<p>162.158.234.58: clarify</p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Unless you want to go completely nuts on this topic, avoid reading Jane Austen, where the the term "X-in-law" is used to mean, roughly, "someone to whom you are related for legal reasons". It can be used to refer to, for example, what we today might refer to as step/half-siblings, adopted siblings, etc. [[User:Arcanechili|Arcanechili]] ([[User talk:Arcanechili|talk]]) 15:51, 31 August 2018 (UTC)<br />
<br />
> The title text refers to incestual relationships, which are generally frowned upon in Western culture.<br />
How on earth this refers to incest if persons are only legally, not genetically related??? It's just that Randall doesn't know how to call new relatives but cannot stop their arrival. {{unsigned ip|162.158.91.251}}<br />
<br />
Yes, I also don't think it refers to incest. {{unsigned ip|172.68.94.40}}<br />
<br />
:I'm not sure if that is right or not, but that was my interpretation of that text, based on the "a reason why these two should not be wed." Unless there is a different issue with this, also involving marriage? [[Special:Contributions/162.158.59.190|162.158.59.190]] 16:44, 31 August 2018 (UTC)<br />
<br />
::I read the title text as... the reason he is objecting has nothing to do with the couple getting married, it's simply the selfish reason that Randall doesn't want the confusion of having to figure out what to call the new extended-family members. [[User:N0lqu|-boB]] ([[User talk:N0lqu|talk]]) 17:37, 31 August 2018 (UTC)<br />
<br />
Somehow I don't have this problem whatsoever...as I'm a single child who married a single child. I have zero siblings-in-law. In fact, my future kids won't even have (regular) cousins... {{unsigned ip|162.158.74.231}}<br />
<br />
Am I the only one that thinks there's an error in this comic? Shouldn't spouse's sibling be the sibling-in-law of Cueball's *sibling*? But then, maybe I'm also making Randall's point... [[User:Sspenser|Sspenser]] ([[User talk:Sspenser|talk]]) 18:28, 31 August 2018 (UTC)<br />
<br />
The Russian language actually has different words for both "types" of brothers in-law (spouse's brother vs. sister's husband), also for parents and children in-law on either side: https://ru.wikipedia.org/wiki/Свойство_(родство) .<br />
But all these in-law distinctions are based on the respective spouse's sex, so it would't work for same-sex marriages.</div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=Talk:2040:_Sibling-in-Law&diff=162166Talk:2040: Sibling-in-Law2018-08-31T18:50:20Z<p>162.158.234.58: doesn't distinguish for same-sex marriages</p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Unless you want to go completely nuts on this topic, avoid reading Jane Austen, where the the term "X-in-law" is used to mean, roughly, "someone to whom you are related for legal reasons". It can be used to refer to, for example, what we today might refer to as step/half-siblings, adopted siblings, etc. [[User:Arcanechili|Arcanechili]] ([[User talk:Arcanechili|talk]]) 15:51, 31 August 2018 (UTC)<br />
<br />
> The title text refers to incestual relationships, which are generally frowned upon in Western culture.<br />
How on earth this refers to incest if persons are only legally, not genetically related??? It's just that Randall doesn't know how to call new relatives but cannot stop their arrival. {{unsigned ip|162.158.91.251}}<br />
<br />
Yes, I also don't think it refers to incest. {{unsigned ip|172.68.94.40}}<br />
<br />
:I'm not sure if that is right or not, but that was my interpretation of that text, based on the "a reason why these two should not be wed." Unless there is a different issue with this, also involving marriage? [[Special:Contributions/162.158.59.190|162.158.59.190]] 16:44, 31 August 2018 (UTC)<br />
<br />
::I read the title text as... the reason he is objecting has nothing to do with the couple getting married, it's simply the selfish reason that Randall doesn't want the confusion of having to figure out what to call the new extended-family members. [[User:N0lqu|-boB]] ([[User talk:N0lqu|talk]]) 17:37, 31 August 2018 (UTC)<br />
<br />
Somehow I don't have this problem whatsoever...as I'm a single child who married a single child. I have zero siblings-in-law. In fact, my future kids won't even have (regular) cousins... {{unsigned ip|162.158.74.231}}<br />
<br />
Am I the only one that thinks there's an error in this comic? Shouldn't spouse's sibling be the sibling-in-law of Cueball's *sibling*? But then, maybe I'm also making Randall's point... [[User:Sspenser|Sspenser]] ([[User talk:Sspenser|talk]]) 18:28, 31 August 2018 (UTC)<br />
<br />
The Russian language actually has different words for both "types" of brothers in-law (spouse's brother vs. sister's husband), also for parents and children in-law on either side: https://ru.wikipedia.org/wiki/Свойство_(родство)<br />
But all in-law terms are linked to the respective spouse's sex, so it wouldn't work for same-sex marriages.</div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=Talk:2040:_Sibling-in-Law&diff=162163Talk:2040: Sibling-in-Law2018-08-31T18:38:49Z<p>162.158.234.58: Russian language disambiguates these</p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Unless you want to go completely nuts on this topic, avoid reading Jane Austen, where the the term "X-in-law" is used to mean, roughly, "someone to whom you are related for legal reasons". It can be used to refer to, for example, what we today might refer to as step/half-siblings, adopted siblings, etc. [[User:Arcanechili|Arcanechili]] ([[User talk:Arcanechili|talk]]) 15:51, 31 August 2018 (UTC)<br />
<br />
> The title text refers to incestual relationships, which are generally frowned upon in Western culture.<br />
How on earth this refers to incest if persons are only legally, not genetically related??? It's just that Randall doesn't know how to call new relatives but cannot stop their arrival. {{unsigned ip|162.158.91.251}}<br />
<br />
Yes, I also don't think it refers to incest. {{unsigned ip|172.68.94.40}}<br />
<br />
:I'm not sure if that is right or not, but that was my interpretation of that text, based on the "a reason why these two should not be wed." Unless there is a different issue with this, also involving marriage? [[Special:Contributions/162.158.59.190|162.158.59.190]] 16:44, 31 August 2018 (UTC)<br />
<br />
::I read the title text as... the reason he is objecting has nothing to do with the couple getting married, it's simply the selfish reason that Randall doesn't want the confusion of having to figure out what to call the new extended-family members. [[User:N0lqu|-boB]] ([[User talk:N0lqu|talk]]) 17:37, 31 August 2018 (UTC)<br />
<br />
Somehow I don't have this problem whatsoever...as I'm a single child who married a single child. I have zero siblings-in-law. In fact, my future kids won't even have (regular) cousins... {{unsigned ip|162.158.74.231}}<br />
<br />
Am I the only one that thinks there's an error in this comic? Shouldn't spouse's sibling be the sibling-in-law of Cueball's *sibling*? But then, maybe I'm also making Randall's point... [[User:Sspenser|Sspenser]] ([[User talk:Sspenser|talk]]) 18:28, 31 August 2018 (UTC)<br />
<br />
Russians actually have different words for both "types" of brothers in-law (spouses brother vs. sisters husband), also for parents or children in-law on either side: https://ru.wikipedia.org/wiki/%D0%A1%D0%B2%D0%BE%D0%B9%D1%81%D1%82%D0%B2%D0%BE_(%D1%80%D0%BE%D0%B4%D1%81%D1%82%D0%B2%D0%BE)</div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=Talk:2005:_Attention_Span&diff=158660Talk:2005: Attention Span2018-06-11T09:51:58Z<p>162.158.234.58: </p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Do you think the book being referenced is a Dragon Lance book?[[Special:Contributions/162.158.106.24|162.158.106.24]] 04:33, 11 June 2018 (UTC)<br />
<br />
The comic contains a hyperlink to what appears to be exactly the kind of article Cueball apparently "''just'' finished reading", or at least my mobile reader is picking up a hyperlink. I've added a small note about this; I'm not linking the article directly for personal reasons. [[Special:Contributions/108.162.221.227|108.162.221.227]] 05:51, 11 June 2018 (UTC)<br />
: I linked it. If it's linked in the original then it should be here, too. Maybe it belongs more to the trivia section, I don't know, but it definitely has to be shown here somewhere. On a side node: did Randall ever do something like that before? [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:53, 11 June 2018 (UTC)<br />
:: Linking other content behind the image? Yes, I think he did it several times before. The only actual comic I remember, however, is [[351: Trolling]]. --[[User:YMS|YMS]] ([[User talk:YMS|talk]]) 09:17, 11 June 2018 (UTC)<br />
:Considering that the link contains a link to this https://www.youtube.com/watch?v=jltKnDlH_OA I believe that omission is no an option [[Special:Contributions/162.158.234.58|162.158.234.58]] 09:51, 11 June 2018 (UTC)</div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=1381:_Margin&diff=1455781381: Margin2017-09-17T15:51:22Z<p>162.158.234.58: added note on font size reduction on real paper</p>
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<div>{{comic<br />
| number = 1381<br />
| date = June 13, 2014<br />
| title = Margin<br />
| image = margin.png<br />
| titletext = PROTIP: You can get around the Shannon-Hartley limit by setting your font size to 0.<br />
}}<br />
<br />
==Explanation==<br />
<br />
This is a reference to {{w|Fermat's Last Theorem}}, of which {{w|Pierre de Fermat}} claimed he had a proof that was too large to fit in the margin of a copy of ''{{w|Arithmetica}}''. Despite its simple formulation, the problem remained unsolved for three centuries; it was cracked only with advanced techniques developed in the 20th century, leading many to believe that Fermat didn't actually possess {{w|Fermat's Last Theorem#Fermat's conjecture|a (correct) proof}} (see [[#trivia|trivia]]).<br />
<br />
In the comic, the person writing in the margin attempts to pull a similar trick, without actually having any proof, by claiming that he has found a proof that information is infinitely compressible, but pretending not to be able to show it due to lack of space in the margin. In this particular case, however, this approach backfires, precisely because if information was actually infinitely compressible, the writer ''would'' be able to fit the proof in the margin (due to his own proof). The writer realizes that if he had a proof he should be able to fit it into the margin, and thus he realizes that he cannot pull this trick. Or perhaps the writer really thought he had a proof, but then realized that his statement was a counterexample, and was disappointed that his idea for a proof was wrong.<br />
<br />
What it seems he did not realize, is that it would be impossible to read the proof if the writer actually was able to compress his proof to fit in the margin. This is because you would need to know the algorithm described in the proof before you could decompress the proof text so you can read it. So he could actually have used this trick instead, writing that he had compressed it into - say a dot "'''.'''" - and then people would have to find his proof to read it. And since they cannot find such a proof - they could not check his dot. Unfortunately this would also have backfired - because there is already a {{w|Pigeonhole principle#Uses and applications|proof that this is not possible}}!<br />
<br />
Another thing that he probably didn't realize, is that finding a proof for something being possible does not necessarily mean inventing an actual algorithm to do that particular thing. If the person claimed having found a {{w|Constructive proof|non-constructive proof}} for such an algorithm, his statement at least wouldn't contradict itself.<br />
<br />
The title text, yet another [[:Category:Protip|protip]], makes a reference to the {{w|Shannon–Hartley theorem}}, which limits the maximum rate at which information can be transmitted. Setting the font size of text only changes its ''representation'' on the screen, and not the actual characters themselves. Trying to decrease the amount of space needed to store or transmit it like advised would be nonsensical. Another possible interpretation is that if you set the font size to 0, the text cannot be seen, and therefore, nothing is being transmitted period.<br />
<br />
In the case of actual printed paper, decreasing the font size is valid technique for information compression (more information on the same page), as used in ie. {{w|microform}}. However, this comes at the cost of an increased spatial bandwidth (number of black/white transitions per distance). In the end, the resolution of the printer/paper/microscope chain limits the minimal font size that remains useable (above the {{w|Nyquist rate}}).<br />
<br />
==Transcript==<br />
:[Written on the right margin of a page:]<br />
:I have<br />
:discovered<br />
:a truly<br />
:marvelous<br />
:proof that<br />
:information<br />
:is infinitely<br />
:compressible,<br />
:but this<br />
:margin is too<br />
:small to...<br />
<br />
:...oh<br />
<br />
:never mind :(<br />
<br />
==Background to Fermat's Last Theorem==<br />
<br />
*Fermat's Last Theorem states that no three positive integers ''a'', ''b'', and ''c'' can satisfy the equation ''a''<sup>''n''</sup> + ''b''<sup>''n''</sup> = ''c''<sup>''n''</sup> for any integer value of ''n'' greater than two.<br />
**In the case with n=2, a b and c are the sides of a {{w|Pythagorean theorem|right triangle}}. There are an infinite number of integer solutions for a, b and c, such as ''3''<sup>''2''</sup> + ''4''<sup>''2''</sup> = ''5''<sup>''2''</sup>. This was known to Euclid.<br />
*Fermat's Last Theorem was {{w|Wiles' proof of Fermat's Last Theorem|solved}} in 1995 by {{w|Andrew Wiles}} with some assistance by {{w|Richard Taylor (mathematician)|Richard Taylor}} who helped him close a gap in his original proof from 1993.<br />
**The proof involved some of the most complicated mathematics used today, and it has been speculated that only a handful of people in the world would be able to understand it.<br />
**For people interested in the subject, {{w|Simon Singh}} has written a [http://simonsingh.net/books/fermats-last-theorem/the-book/ popular science book] about it, called ''{{w|Fermat's Last Theorem (book)|Fermat's Last Theorem}}''.<br />
***[https://www.youtube.com/watch?v=qiNcEguuFSA Fermat's Last Theorem - Numberphile]<br />
***[https://www.youtube.com/watch?v=FXbsIbRVios Fermat's Last Theorem (extra footage) - Numberphile]<br />
*There are US Patents in this very area, analyzed by [http://gailly.net/05533051.html Jean-loup Gailly].<br />
<br />
{{comic discussion}}<br />
[[Category:Protip]]<br />
[[Category:Math]]<br />
--DrMath 06:10, 18 October 2016 (UTC)</div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=User:Dgbrt&diff=144762User:Dgbrt2017-08-30T10:37:25Z<p>162.158.234.58: /* I'm not a native English speaker */</p>
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<div>Hello, I am a big xkcd fan.<br />
<br />
====My introduction as xkcd fan====<br />
My random list of favourite Comics by Randall:<br />
[[Combination Vision Test]],<br />
[[Up_Goer_Five]]<br />
and of course that tiny rover never coming home:<br />
[[Spirit]]<br />
<br />
====I'm ''not'' a native English speaker====<br />
...and I don't like "typos". So much THANKS for helping on this issue or even more importantly: Wrong grammar <-I don't like these errors I don't see.<br />
<br />
As a German native speaker I had to learn something like "Oxford English" in school, and I hated it. My knowledge about the (American, British, more...) English language mostly belongs to later experiences. International contacts, science (especially physics), programming (Randall does not know how funny IBM's translations for German are - "Copy from to" becomes "Copy until") in German, '''''AND''''' the main language on the Internet is, of course, English.<br />
<br />
Also I was even bad on the German language sessions at school. But that's just another story.<br />
<br />
I'm happy about corrections on my typos and grammar, but on essential content I will discuss.<br />
<br />
Thanks to [[User: Spongebog|Spongebob]] for some smaller edits on this page. I'm still learning English...<br /><br />
Thanks to [[User: Spongebog|Spongebob]] again for fixing a really damn typo...<br />
<!--If you don't like my changes,you are free to revert them —Artyer --></div>162.158.234.58https://www.explainxkcd.com/wiki/index.php?title=1878:_Earth_Orbital_Diagram&diff=1443801878: Earth Orbital Diagram2017-08-22T12:24:09Z<p>162.158.234.58: /* Labels and Their Astronomical Meanings */ Link to the wp page for Triple Goddess.</p>
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<div>{{comic<br />
| number = 1878<br />
| date = August 18, 2017<br />
| title = Earth Orbital Diagram<br />
| image = earth_orbital_diagram.png<br />
| titletext = You shouldn't look directly at a partial eclipse because of the damage that can be caused by improperly aligning the solar-lunar orbital plane with the orbital bones around your eye.<br />
}}<br />
<br />
==Explanation==<br />
This comic is the third consecutive comic published in the week before the {{w|solar eclipse}} occurring on Monday, {{w|Solar eclipse of August 21, 2017|August 21, 2017}} which is a total solar eclipse and visible in totality within a band across the {{w|contiguous United States}} from west to east. The other comics are [[1876: Eclipse Searches]] and [[1877: Eclipse Science]]. The trend continued on the day of the eclipse with [[1879: Eclipse Birds]].<br />
<br />
The comic claims that the reason that eclipses don't happen every month is simple to understand by looking at an orbital diagram. Ironically, the cartoon has so many parts and labels that it is far more difficult to understand than is implied. While the graph itself is based on {{w|Orbital elements|astronomical definitions}}, all the labels are nonsense in this context. In effect, the comic is a new take on a common joke in which a person asks a scientist a question, the scientist begins by saying "It's really quite simple", then proceeds to give a very lengthy and highly technical explanation that non-scientists would not be expected to understand.<br />
<br />
All of the labels in the diagram are complicated words or phrases. Some are related to orbital mechanics (e.g. "equinox" and "perihelion"), while others are wholly unrelated or even made up. Each label is nonsensical in its place in the diagram. Compare/contrast with the standard {{w|Kepler orbit|Kepler Orbit}} diagram.<br />
<br />
The title text references warnings to not look directly into the sun, but parodies those warnings by referring to 'orbit', the anatomical term for the eye socket.<br />
<br />
===Labels and Their Astronomical Meanings===<br />
<br />
;Arctangent<br />
*{{w|Arctangent}} is the inverse function of the tangent function of trigonometry. You can determine a non-right angle of a right triangle by taking the arctangent of the length of the opposite side divided by the length of the adjacent side.<br />
*The angle shown in the comic has no astronomical meaning.<br />
<br />
;Astral plane<br />
*The {{w|Astral plane}} is a plane of existence in various esoteric theories. It features prominently in {{w|Dungeons & Dragons}} cosmology, connecting the various other planes of existence.<br />
*The picture shows the {{w|Orbit_of_the_Moon|lunar orbital plane}}, the plane in which the Moon orbits the Earth, tilted about 5.1 degrees from the ecliptic.<br />
<br />
;Declension<br />
*{{w|Declension}} is the inflection of nouns in a language. In {{w|Latin}} declension and declination are both called ''{{w|la:Declinatio|Declinatio}}''. In this comic, however, it might be a portmanteau of declination and (right) ascension.<br />
*In astronomy, the {{w|Declination|declination}} is one of the two angles that locate a point on the celestial sphere in the equatorial coordinate system. It is measured north or south of the celestial equator, like the geographical latitude on Earth. But in the picture the label is at the angle for the axial tilt of the Earth.<br />
*And the {{w|Right_ascension|right ascension}} is the angular distance measured eastward along the celestial equator from the vernal equinox to the hour circle of the point in question.<br />
<br />
;Determinant of the date of Easter<br />
*In Western Christianity {{w|Easter}} always falls on the first Sunday after the first ecclesiastical full moon after the beginning of spring (equinox). The ecclesiastical full moon is determined by a calendar that approximates the actual time of the full moon, Thus the date of easter is defined by a combination of a solar and a lunar calendar. The position of that angle isn't that bad but it should be not more than 30 degrees (slightly more than one month.)<br />
*In mathematics, the determinant is a function of numerical matrices. In this context, however, it apparently refers to something that directly determines the date of Easter.<br />
<br />
;Dimples of Venus<br />
*The {{w|Dimples of Venus}} are indentations sometimes visible on the human lower back.<br />
*In astronomy the {{w|Belt of Venus}} is a shadow cast by the Earth visible in its atmosphere.<br />
<br />
;Enceliopsis<br />
*{{w|Enceliopsis}} are small genus of flowering plants in the daisy family, appropriately known as "sunrays".<br />
*In astronomy this point has also no specific meaning. But {{w|Enceladus}} is a moon around {{w|Saturn}}.<br />
<br />
;Equinox / Solstice<br />
{{w|Equinox}} and {{w|Solstice}} have very different meanings:<br />
*An Equinox is one of two instants in the year when the sun is exactly over the equator; the length of day and night are very nearly equal that day at all locations on the planet, and (in the United States) it is the first day of Spring or Autumn, depending on the time of year.<br />
*A Solstice is one of two instants in the year when the sun's angle is maximally far from Earth's equator; when one occurs, the length of the day or night is shortest or longest (depending on whether one is in the northern or southern hemisphere), and (in the United States) it marks the first day of summer or winter.<br />
<br />
Both types occur because the Earth's rotation axis is tilted (at 23.4 degrees) from its orbital plane (ecliptic) about the Sun.<br />
<br />
Jokingly insisting that two different terms are American/British variants of the same word has been the topic of [[1677: Contrails]].<br />
<br />
;Hypothecate<br />
*{{w|Hypothecate}} is a legal verb that means something similar to "make a mortgage".<br />
*The {{w|hypotenuse}} is the longest side of a right-angled triangle. Here it is an unrelated length, approximately equal to the diameter of the sun (half the angular size of the sun times twice the distance to it).<br />
<br />
;Obsequity<br />
*Obsequity means the state of being obsequious (showing an indecorous willingness to obey or serve, or "sucking up").<br />
*In astronomy the correct word is {{w|Obliquity}}, meaning an axial tilt.<br />
<br />
;Perihelix<br />
*This is a portmanteau of helix and perihelion.<br />
*The {{w|perihelion}} is the point in a elliptical solar orbit that is closest to the Sun.<br />
<br />
;Prolapse<br />
*A {{w|Prolapse}} is a medical condition in which an internal organ is slipped forward or down.<br />
*{{w|Retrograde and prograde motion}} are terms used to describe the apparent motion of celestial objects through the sky. <br />
<br />
;Sagittal plane<br />
*The {{w|Sagittal plane}} is an anatomical plane, dividing the body in left and right.<br />
*The correct label in the picture would be the {{w|Ecliptic plane}}. The plane the Earth orbits the Sun.<br />
*{{w|Sagittarius (constellation)|Sagittarius}} is one of the stellar constellations of the Zodiac. The center of the Milky Way lies in this constellation.<br />
<br />
;Solar plexus<br />
*The {{w|Solar plexus}} is a network of nerves located in the abdomen. It was the name of [[64: Solar Plexus]].<br />
*{{w|Solar}} is an adjective referring to the Sun, the star in our solar system.<br />
<br />
;Tropopause<br />
*The {{w|Tropopause}} is the boundary in our atmosphere between the troposphere and stratosphere, defined as the boundary where air ceases to cool with increasing elevation. It is 9-17 km above sea level, not the thousands of kilometers as depicted here.<br />
*The label appears to point at the orbit of the moon.<br />
<br />
;Angle between the Astral and the Sagittal Planes<br />
* The angle depicted is the inclination of the moon orbit. The planes are marked with the symbol for the Capricorn zodiac sign and the symbol of {{w|Triple Goddess (Neopaganism)|The Triple Goddess}}; the angle is marked with the greek letter ''phi'' (ϕ), except with two vertical lines (as if it was a currency unit, similarly to the euro sign).<br />
<br />
;Errata<br />
* Errata are corrections in a published text (e.g. a newspaper article) issued after the publication.<br />
* The angle depicted as errata is half the angular size of the sun, which has to match the lunar angular size to cause a solar total eclipse.<br />
<br />
==Explanation for "Why isn't there a (solar) eclipse every month?"==<br />
<br />
If the plane of where the Earth orbits the Sun and where the Moon orbits the Earth were completely aligned, then there would be a solar eclipse at every new moon (once every {{w|Orbit_of_the_Moon#Lunar_periods| 29.5 days}}) and a lunar eclipse at every full moon (half a lunar period about 14.7 days after a New Moon). However, the plane in which the Moon orbits the Earth is tilted with an inclination of 5 degrees relative to that of the ecliptic plane (the plane defined by the Earth's orbit around the Sun). Eclipses are only possible during two eclipse seasons each year (half a year apart) where for a period of 31 to 37 days the Sun is nearly aligned with the two points in the tilted Earth-Moon plane where the Moon crosses the ecliptic plane. During an eclipse season at the time of a new moon there will be solar eclipses visible from certain locations and during full moons there will be lunar eclipses.<br />
<br />
[[Image:Eclipse_Diagram.jpg]]<br />
<br />
The real explanation of eclipses is evident from this xkcd comic, but is labeled with a fictional character similar to a Greek phi but with two vertical lines; the remaining labels also do not contribute to this explanation and exist only to distract or misinform or entertain the reader.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
:[An orbital map of the Earth is shown. The Sun is in the center, the Earth is at the right bottom, and the Moon is left below the Earth.]<br />
:'''Why isn't there an eclipse every month?'''<br />
:This is a common question! The answer is made clear by a quick look at the Earth's orbital diagram:<br />
<br />
:[Label Sun:]<br />
:Solar plexus<br />
<br />
:[Label on the Earth's plane:]<br />
:Sagittal plane<br />
<br />
:[Labels on Earth's orbit (beginning at the Earth counterclockwise):]<br />
:Perihelix, Declension, Obsequity, Hypothecate, Enceliopsis, Equinox (''Solstice'' in British English)<br />
<br />
:[Two angles in the plane are labeled as:]<br />
:Determinant of the date of Easter, Arctangent<br />
<br />
:[The plane of the Moon is pictured in a small angle to the Earth's plane and named Astral Plane. The angle is presented between two lines (Greek Nu or Gamma and a double Greek Chi) and identified by a "Game Of Thrones" 'O' (a character that looks similar to a Greek Phi but with two vertical lines).]<br />
:[The labels at the Moon's path are:]<br />
:Tropopause, Prolapse, Errata.<br />
<br />
:[An arrow points to the Earth at the zero meridian on the equator. The label reads:]<br />
:Dimples of Venus<br />
<br />
{{comic discussion}}<br />
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[[Category:Astronomy]]</div>162.158.234.58