explain xkcd - User contributions [en]

2265: Tax AI

2020-02-07T17:51:17Z

172.68.189.175: /* Explanation */

{{comic
| number = 2265
| date = February 7, 2020
| title = Tax AI
| image = tax_ai.png
| titletext = I ended up getting my tax return prepared at a local place by a really friendly pretrained neural net named Greg.
}}

==Explanation==
{{incomplete|Needs explanation for "Seitan"}}

In this comic, Cueball has attempted to train a neural net to prepare his U.S. Tax Return, but it has made several comical errors, purportedly because it was not trained extensively enough. Most of the errors consist of {{w|Malapropisms}}, words that sound almost the same but mean very different things switched for comic effect. This suggests Cueball trained the neural net by talking to it.
* It suggests that Cueball could claim 1040 defendants. Typically, taxpayers may claim "dependents" (not "defendants"), and these correspond to children or others for whom the taxpayer is the primary caregiver, so 1040 would be an absurdly high number {{Citation needed}}. 1040, however is the number of the primary tax document that must be filed.
* It mentions fiscal year 20202, presumably because it got carried away with 2's and 0's in 2020. However, at the date the comic was published, Cueball should be filing his 2019 taxes anyway. Alternately, the comic could place in the future and it took the way most people will speak the year 2020 ("twenty twenty-two") and then transferred this directly to numbers ("20" "20" "2" becoming 20202).
* It suggests taking the "standard deduckling" instead of the "standard deduction", which is what many taxpayers opt to do rather than attempting to itemize their deductions (which can lead to a greater deduction but requires more effort and supporting documentation).
* It also suggests "atomizing" his "clams" instead of "itemizing" his "claims" which, as mentioned above, wouldn't make sense if he was taking the standard deduction anyway.

The title text references https://xkcd.com/2173/, which indicates that getting a human to do something is basically using a "pretrained neural net".

==Transcript==
:[Cueball sits at a desk using a laptop.]
:Laptop: You may claim up to 1040 defendants on your seitan local income tax for fiscal year 20202 by taking the standard deduckling and atomizing your clams.

:[Caption below the panel:]
:I used a neural net to prepare my tax returns, but I think I cut off its training too early.
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

2265: Tax AI

2020-02-07T17:50:35Z

172.68.189.175: /* Explanation */

{{comic
| number = 2265
| date = February 7, 2020
| title = Tax AI
| image = tax_ai.png
| titletext = I ended up getting my tax return prepared at a local place by a really friendly pretrained neural net named Greg.
}}

==Explanation==
{{incomplete|Needs explanation for "Seitan"}}

In this comic, Cueball has attempted to train a neural net to prepare his U.S. Tax Return, but it has made several comical errors, purportedly because it was not trained extensively enough. Most of the errors consist of Malapropisms, words that sound almost the same but mean very different things switched for comic effect. This suggests Cueball trained the neural net by talking to it.
* It suggests that Cueball could claim 1040 defendants. Typically, taxpayers may claim "dependents" (not "defendants"), and these correspond to children or others for whom the taxpayer is the primary caregiver, so 1040 would be an absurdly high number {{Citation needed}}. 1040, however is the number of the primary tax document that must be filed.
* It mentions fiscal year 20202, presumably because it got carried away with 2's and 0's in 2020. However, at the date the comic was published, Cueball should be filing his 2019 taxes anyway. Alternately, the comic could place in the future and it took the way most people will speak the year 2020 ("twenty twenty-two") and then transferred this directly to numbers ("20" "20" "2" becoming 20202).
* It suggests taking the "standard deduckling" instead of the "standard deduction", which is what many taxpayers opt to do rather than attempting to itemize their deductions (which can lead to a greater deduction but requires more effort and supporting documentation).
* It also suggests "atomizing" his "clams" instead of "itemizing" his "claims" which, as mentioned above, wouldn't make sense if he was taking the standard deduction anyway.

The title text references https://xkcd.com/2173/, which indicates that getting a human to do something is basically using a "pretrained neural net".

==Transcript==
:[Cueball sits at a desk using a laptop.]
:Laptop: You may claim up to 1040 defendants on your seitan local income tax for fiscal year 20202 by taking the standard deduckling and atomizing your clams.

:[Caption below the panel:]
:I used a neural net to prepare my tax returns, but I think I cut off its training too early.
{{incomplete transcript|Do NOT delete this tag too soon.}}

{{comic discussion}}

2172: Lunar Cycles

2019-07-07T09:26:17Z

172.68.189.175: /* Explanation */ detail

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**A [[wikipedia:Supermoon|supermoon]] is a full or new moon when the Moon is closest to the Earth, resulting in a slightly larger-than-usual apparent size. A full supermoon is roughly 14% larger in diameter than when the Moon is furthest away. See also [[1394: Superm*n]].
**A [[wikipedia:blue moon|blue moon]] is the extra full moon in years with 13 full moons. An event that occurs once every two or three years. Blue moons don't look any different from regular full moons.
**{{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. The '''two-week window in which astrology works''' is a joke about how astrology does not actually work but occasionally seems to work by sheer coincidence.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**There are no occurrences of '''super blood moon''', '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer, which includes many works from the 1800s through 2008. A [[wikipedia:blood moon|blood moon]] refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' ([[wikipedia:Slim-fit pants|slim-fit pants]]) does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Finally, while the idea of a '''total eclipse of the sea''' seems absurd, [https://www.deepseanews.com/2017/08/what-happens-in-the-sea-during-a-solar-eclipse/ an eclipse was famously used to explain the migration of maritime animals]:
:::''biologists were beginning to unravel the mystery of this ‘false bottom’–a layer in the ocean that looks the the sea floor on the sounder but isn’t–which covered much of the ocean. This false bottom rises in up at night and sinks down during the day. This rising and falling is in fact caused by the largest migration of animal on Earth–everything from fish, shrimp and jellyfish, moving hundreds of meters in unison up and down each day.... the moon moved into its place in front of the sun, daylight rapidly faded, and the scientists solved the migration mystery: the deep layer of animals began to rise. Bioluminescent creatures started to shine, and nocturnal creatures started a frantic upward thrust. As the world grew darker, they swam upward nearly 80 meters. But this frantic migration didn’t last long. As the moon receded and the sun revealed itself, the massive animal layer did an about-face, scrambling back into the safety of the darkness.''
:: (Backus, Clark, and Wing (1965) [https://sci-hub.tw/10.1038/205989a0 "Behaviour of certain marine organisms during the solar eclipse of July 20, 1963"] ''Nature'' '''4975:'''989-91.)
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-07T09:21:09Z

172.68.189.175: /* Explanation */ quote, expand

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**[[wikipedia:Supermoon|Supermoon]]: see [[1394: Superm*n]].
**A [[wikipedia:blue moon|blue moon]] is the extra full moon in years with 13 full moons. An event that occurs once every two or three years. Blue moons don't look any different from regular full moons.
**{{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. The '''two-week window in which astrology works''' is a joke about how astrology does not actually work but occasionally seems to work by sheer coincidence.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**There are no occurrences of '''super blood moon''', '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer, which includes many works from the 1800s through 2008. A [[wikipedia:blood moon|blood moon]] refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' ([[wikipedia:Slim-fit pants|slim-fit pants]]) does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Finally, while the idea of a '''total eclipse of the sea''' seems absurd, [https://www.deepseanews.com/2017/08/what-happens-in-the-sea-during-a-solar-eclipse/ an eclipse was famously used to explain the migration of maritime animals]:
:::''biologists were beginning to unravel the mystery of this ‘false bottom’–a layer in the ocean that looks the the sea floor on the sounder but isn’t–which covered much of the ocean. This false bottom rises in up at night and sinks down during the day. This rising and falling is in fact caused by the largest migration of animal on Earth–everything from fish, shrimp and jellyfish, moving hundreds of meters in unison up and down each day.... the moon moved into its place in front of the sun, daylight rapidly faded, and the scientists solved the migration mystery: the deep layer of animals began to rise. Bioluminescent creatures started to shine, and nocturnal creatures started a frantic upward thrust. As the world grew darker, they swam upward nearly 80 meters. But this frantic migration didn’t last long. As the moon receded and the sun revealed itself, the massive animal layer did an about-face, scrambling back into the safety of the darkness.''
:: (Backus, Clark, and Wing (1965) [https://sci-hub.tw/10.1038/205989a0 "Behaviour of certain marine organisms during the solar eclipse of July 20, 1963"] ''Nature'' '''4975:'''989-91.)
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-07T09:15:33Z

172.68.189.175: /* Explanation */ total eclipse of the sea

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not actually work but occasionally seems to by coincidence.
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**A [[wikipedia:blue moon|blue moon]] is the extra full moon in years with 13 full moons. An event that occurs once every two or three years. Blue moons don't look any different from regular full moons.
**There are no occurrences of '''super blood moon''', '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer, which includes many works from the 1800s through 2008. A [[wikipedia:blood moon|blood moon]] refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' ([[wikipedia:Slim-fit pants|slim-fit pants]]) does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Finally, while the idea of a '''total eclipse of the sea''' seems absurd, [https://www.deepseanews.com/2017/08/what-happens-in-the-sea-during-a-solar-eclipse/ an eclipse was famously used to explain the migration of maritime animals.] (Backus, Clark, and Wing (1965) [https://sci-hub.tw/10.1038/205989a0 "Behaviour of certain marine organisms during the solar eclipse of July 20, 1963"] ''Nature'' '''4975:'''989-91.)
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-06T22:58:24Z

172.68.189.175: /* Explanation */ reorder

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not work (or rarely works).
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**There are no occurrences of '''super blood moon''', '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer, which includes many works from the 1800s through 2008. A [[wikipedia:blood moon|blood moon]] refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' does change over time, the idea that this is connected to a lunar cycle is also a joke.
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

Talk:2172: Lunar Cycles

2019-07-06T22:56:49Z

172.68.189.175: /* Lunar Mood smile/frown concavity orientation mismatch */ withdrawn

Is it possible that the size of the Earth and the moon are supposed to be comparisons of how big the Earth looks from the moon vs. how big the moon looks from the Earth? {{unsigned ip|172.69.170.88}}
:Why would that have a cycle different from the distance cycle?[[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 20:20, 5 July 2019 (UTC)

Where is the total eclipse of the heart?
Actually, why do we not have a total eclipse of the hart - when all deer are hidden?

A very quick and dirty (probably flawed, until I can plug things into a suitable visualiser to check and/or improve my initial idea) attempt to describe the nature of the square/circle oscilations of the Moon might well be smething like ''|r.cos(θ)−r.sin(θ)|.|sin(t/λ)| + |r.cos(θ)+r.sin(θ)|.|sin(t/λ)| + |r.√(2/π)|.|cos(t/λ)|=k'' ...only then you'd also want to make k a quantity also multiplied by the relative Earth/Moon size cycle. Either way, YMoonMV. [[Special:Contributions/141.101.98.88|141.101.98.88]] 00:41, 6 July 2019 (UTC)
:Isn't the square/circle a reference to rounded corner rectangles. If you increase the corner radius of a square, enough, you get a circle. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 05:37, 6 July 2019 (UTC)

Does anyone know of a real chart similar to the format of the last panel? That might be a cool thing to link to.
[[Special:Contributions/162.158.75.166|162.158.75.166]] 16:38, 6 July 2019 (UTC)

== Astrology ==
I think this is primarily an astrology joke. Astrologers often use astronomical cycles (both real and made up) to "predict" future events or explain historic events. By having enough cycles, they can usually come up with results like "skinny jeans are always popular whenever the happy moon is in Pices and wet Mars is in the same Chinese zodiac as Mercury".

There's also possibly an allusion to Fourier transforms.

==Phase x distance and supermoons==
I've been absolutely nerd-sniped by the "Phase x distance" in the bottom diagram. As far as I can figure out, if you multiply phase and distance, you should end up with a new cycle with a period of (29.5 x 27.5) = 811.25 days, which is about 2 years. A supermoon is when a full moon occurs when the Moon is closest to the Earth, so this phase x distance figure is effectively a supermoon detector - that's why supermoons occur at the peaks in Randall's diagram.

But when I looked into supermoons a bit - specifically [https://en.wikipedia.org/wiki/Supermoon#/media/File:Moon_distance_with_full_&_new.png this diagram from Wikipedia] - other sources shows supermoons occurring on a ''yearly'' cycle - we supposedly get them every year. How can that be the case, if the two lunar cycles only synchronize every 2 years? It seems to me like there has to be at least one out of every two years where we get no supermoons at all - ie. the full moon is always coinciding with the moon being furthest away.

I feel like I must have made a mistake or wrong assumption, but I can't figure out what it is. [[User:Hawthorn|Hawthorn]] ([[User talk:Hawthorn|talk]]) 17:15, 6 July 2019 (UTC)
:I figured it out; it turns out that I was simply wrong about how to calculate the length of a combined cycle. This [https://www.desmos.com/calculator/vaj4vapdul graph] shows that the two cycles would coincide every 400 days or so. Still can't figure out what "phase x distance" is meant to represent, though. [[User:Hawthorn|Hawthorn]] ([[User talk:Hawthorn|talk]]) 17:54, 6 July 2019 (UTC)

2172: Lunar Cycles

2019-07-06T22:55:41Z

172.68.189.175: /* Explanation */ revise

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**While the popularity of '''skinny jeans''' does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not work (or rarely works).
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**There are no occurrences of '''super blood moon''', '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer, which includes many works from the 1800s through 2008. A [[wikipedia:blood moon|blood moon]] refers to the moon during a lunar eclipse.
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-06T22:52:59Z

172.68.189.175: /* Explanation */ +2

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**'''Super blood moon:''' a blood moon refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not work (or rarely works).
**A [[wikipedia:harvest moon|harvest moon]] is full moon closest to the autumnal equinox, possibly orange.
**The [[wikipedia:Golden Age of Television|Golden Age of Television]] is said to have occurred in the 1940s and 50s, and the 2000s.
**There are no occurrences of '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer.
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-06T22:47:25Z

172.68.189.175: /* Explanation */ bold

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**'''Super blood moon:''' a blood moon refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not work (or rarely works).
**There are no occurrences of '''dire moon''' or '''pork moon''' in the Google Books N-Gram viewer.
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

2172: Lunar Cycles

2019-07-06T22:46:55Z

172.68.189.175: /* Explanation */

{{comic
| number = 2172
| date = July 5, 2019
| title = Lunar Cycles
| image = lunar_cycles.png
| titletext = The Antikythera mechanism had a whole set of gears specifically to track the cyclic popularity of skinny jeans and low-rise waists.
}}

==Explanation==
{{incomplete|Created by a MOONBOT. Joke cycle explanations need to be expanded and title text needs to be explained. Do NOT delete this tag too soon.}}

This comic shows a mixture of real, scientific lunar cycles and cycles that are comedic or fictional in nature.

*'''Nodal precession:''' The Moon's orbital plane is tilted slightly compared to the Earth's orbital plane around the sun (the {{w|ecliptic}}). This tilt is why we don't constantly see eclipses; most of the time, the Moon's orbital plane is tilted higher or lower than the Sun, so they generally don't cross each other. The two points at which these planes ''do'' cross are called {{w|lunar nodes}}. {{w|Nodal precession}} is the gradual rotation of these nodes over time, which for the Moon follows an 18.6 year cycle.

*'''Apsidal precession:''' All orbits have two points where the orbiting body is either closest to, or furthest away from, the thing they are orbiting. These points are called {{w|apsides}}, and the imaginary line between them is called the ''line of apsides''. {{w|Apsidal precession}} is the gradual rotation of this line over time, which occurs in cycles of around 8.9 years for the Moon.

*'''Phase:''' {{w|Lunar phase}} describes the change in shape of the sunlit side of the Moon as viewed from the Earth's surface, which is caused by the changing angle between Moon and Sun as the Moon revolves around the Earth. The cycle of lunar phases takes 29.5 days, a figure referred to as the ''synodic month''.

*'''Distance:''' Because the Moon's orbit around the Earth is elliptical, its distance from the Earth varies slightly over the course of an orbit. This means that the moon's distance also follows a cycle which is the same as the length of one lunar orbit: approximately 27.5 days. This figure is referred to as the ''sidereal month''. Note that the synodic month is (perhaps counterintuituvely) two days ''longer'' than the sidereal month - or to put it another way, it takes 2 more days for the Moon's phases to cycle than it does for the Moon to go around the Earth. This is due to the fact that the Earth is also moving ''around'' the Sun while the phases are going on, which means that the Moon has to spend 2 extra days "catching up" to the point at which the lunar phase cycle can restart.

*'''Earth-Moon relative size''': This is a joke cycle; the Earth and Moon do not change size, nor does the Moon ever become larger than the Earth. This may be playing on the idea that the Moon often ''appears'' to change size due to a various factors; most commonly, this is due to the {{w|Moon illusion}}, which tricks the brain into perceiving the Moon as much larger than it really is. There are also so-called {{w|supermoon}}s, which occur when the full moon coincides with the Moon's closest approach to Earth; these actually ''do'' increase the Moon's apparent size, although by a relatively insignificant amount.

*'''Lunar shape:''' Again, this is a joke cycle; the Moon does not actually change shape. A shape intermediate between circle and square is known as a {{w|squircle}}, a subclass of the {{w|superellipse}}.

*'''Lunar mood:''' The moon does not have a mood, although humans can have moods that fluctuate over time, sometimes with a regularity akin to a cycle. Ironically, the section of the graph that shows a good (i.e. happy) mood has the graph line curving up then down like the mouth of a frown, and for the bad (unhappy) mood it curves down and then up, as in the mouth of a smile.

* The final diagram shows many different cycles superimposed on each other, highlighting areas where several cycles are coinciding. This is likely satirizing the media trend of overhyping astronomical coincidences and giving them grand-sounding names (which get longer and more impressive the more cycles are coinciding).
**'''Supermoon:''' see [[1394:_Superm*n]].
**'''Super blood moon:''' a blood moon refers to the moon during a lunar eclipse.
**While the popularity of '''skinny jeans''' does change over time, the idea that this is connected to a lunar cycle is also a joke.
**Two-week window in which astrology works. {{w|Astrology}} is a pseudoscience which claims that the positions of the celestial bodies can be used to predict human affairs. This is a joke on how astrology does not work (or rarely works).
**There are no occurrences of "dire moon" or "pork moon" in the Google Books N-Gram viewer.
*The '''{{w|Antikythera_mechanism|Antikythera mechanism}}''' mentioned in the title text is an ancient Greek machine, rediscovered in 1901, designed to calculate astronomical positions. The title text jokes that there is a set of gears on said mechanism that is used to predict the popularity of "skinny jeans" and "low-rise waists."

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:Understanding lunar cycles

:Nodal precession
:[A diagram showing a broad cosine-like wave with wavelength labelled as 18.6 years. To the right are two diagrams showing an orbital cycle moving in and out of plane.]

:Apsidal precession
:[A diagram similar to the one above but with a slightly shorter wavelength, labelled as 8.9 years. To the right are two diagrams showing an elliptical orbit around a planet and the same orbit rotated.]

:Phase
:[A diagram similar to those above with a shorter wavelength, labelled as 29.5 days. To the right is a diagram showing four phases of the moon: New, Waxing crescent, Waxinf gibbos, Full.]

:Distance
:[A diagram similar to those above with a shorter wavelength, labelled as 27.5 days. To the right is a diagram showing the distance of the moon from the Earth over time, with distances marked by arrows.]

:Earth-Moon relative size
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Earth bigger' and an arrow pointing to the maximum labelled 'Moon bigger'. To the right are two diagrams of the moon and Earth, one showing the Earth bigger than the Moon and the other showing the Moon bigger than the Earth.]

:Lunar shape
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Circle' and an arrow pointing to the maximum labelled 'Square'. To the right is a diagram showing a circle, a circle transforming into a square with outward arrows at each corner and a square transforming into a circle with inward arrows.]

:Lunar mood
:[A wave with long wavelength with an arrow pointing to the minimum labelled 'Bad' and an arrow pointing to the maximum labelled 'Good'. To the right are four emojis: :), :|, :(, :|]

:[A superimposed graph of all the above waves. Different points on the graph are labelled: Harvest moon, Supermoon, Blue moon, Skinny Jeans popular, Super blood moon, Golden age of TV, Dire moon, Pork moon, Two week window in which astrology works, Total eclipse of the sea.]

{{comic discussion}}

Talk:2172: Lunar Cycles

2019-07-06T22:43:53Z

172.68.189.175: /* Lunar Mood smile/frown concavity mismatch */ specify

Talk:2172: Lunar Cycles

2019-07-06T22:43:16Z

172.68.189.175: /* Lunar Mood smile/frown concavity mismatch */ l.c.

Talk:2172: Lunar Cycles

2019-07-06T22:42:39Z

172.68.189.175: /* Lunar Mood smile/frown concavity mismatch */ new section

Talk:2171: Shadow Biosphere

2019-07-04T03:45:13Z

172.68.189.175: Humor

Just spit-balling here, but here goes: This comic seems to be making a joke between the meaning of "shadow biosphere" and the more common meaning behind "shadow" being something unseen. I think "shadow biosphere" is currently pretty loosely defined and not widely accepted by academics, and it seems to refer simply to organisms that might exist but are not currently being studied widely. In fact to me, the use of the term "shadow" in the name is relatively misleading and simply refers to a possible case of something not understood and/or studied at length, not that it's invisible. Randall appears to be making fun of the name by suggesting it means invisible to normal life as we know it. The title text further pushes this pun by suggesting that a coating of "desert varnish" makes normally visible objects become invisible, as with the buildings where shadow biologists carry out their work. Desert varnish is in fact visible when it is found in appropriate locations on normal objects like rocks - it does not make the rocks invisible! Somehow, I think these ideas need to be incorporated into the explanation. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 17:00, 3 July 2019 (UTC)

The first paragraph of this comic explanation is a verbatim copy from the beginning of the Wikipedia article for shadow biosphere. It seems that we really should include citations when adding something like this. ---diGGdoug {{unsigned ip|172.69.170.28}}

The desert varnish reference in the alt text is because desert varnish is the most likely example of the shadow biosphere. It seems to be doing something at least vaugely like metabolism, concentrating certain minerals far beyond expected by nature. -[[Special:Contributions/162.158.107.67|162.158.107.67]] 19:47, 3 July 2019 (UTC)

This needs an SCP classification. [[Special:Contributions/172.68.189.175|172.68.189.175]] 03:45, 4 July 2019 (UTC)

Do you have a citation for that? Wikipedia article doesn't mention any metabolism. [[Special:Contributions/172.68.38.64|172.68.38.64]] 22:31, 3 July 2019 (UTC)bk

Could "Shadow" be a Babylon 5 reference? -[[Special:Contributions/162.158.214.148|162.158.214.148]] 01:03, 4 July 2019 (UTC)

2170: Coordinate Precision

2019-07-01T22:24:19Z

172.68.189.175: /* Explanation */

{{comic
| number = 2170
| date = July 1, 2019
| title = Coordinate Precision
| image = coordinate_precision.png
| titletext = 40 digits: You are optimistic about our understanding of the nature of distance itself.
}}

==Explanation==
{{incomplete|Created by a CARTOGRAPHER. Provide examples for each table entry. Do NOT delete this tag too soon.}}

Coordinates are data points used to identify a person's location on the planet Earth. However, a given coordinate covers a square region of land, and thus leaves some ambiguity; thus, greater precision requires an increasing count of decimal points in your coordinates. This comic uses this information to roughly identify how precise a given coordinate length might be.

The coordinates at [https://tools.wmflabs.org/geohack/geohack.php?pagename=Cape_Canaveral&params=28.5234_N_80.6830_W_type:landmark_region:US-FL_scale:10000 28.5234°N, 80.6830°W] (in {{w|decimal degrees}} form; in {{w|geographic coordinate system}} form using degrees, minutes, and seconds, 28° 31′ 24.24″N, 80° 40′ 58.8″W) are pointing to the {{w|Rocket Garden}} at {{w|Kennedy Space Center}} in {{w|Merritt Island, Florida}} (usually referred to as '''{{w|Cape Canaveral}}''')—specifically, the tip of the [https://www.kennedyspacecenter.com/-/media/DNC/KSCVC/Blog-Images/Rocket-Garden/rocket-garden-with-labels.ashx?h=860&w=1173&la=en&hash=7B9ADC7AFF5370E462AC98D9651945B806B77B2C Delta] rocket.

The sixth entry in the table, with seven digits of precision, includes the caveat that, while your coordinates map to areas small enough on the Earth's surface to indicate pointing to a specific person in a room, "since you didn't include datum information, we can't tell who". This is a reference to the various ''[https://en.wikipedia.org/wiki/Geodetic_datum geodetic datums]'' or ''geodetic systems'' — different ways of dealing with the fact that the earth is neither perfectly spherical nor perfectly an oblong ellipsoid. The various datums do not make much difference at six digits of precision, but at seven, there is enough skew depending on which system is in use that the person in a room you are referring to with the coordinates is ambiguous. It is unstated, but the remaining lines in the table with ever-greater precision suffer from this same issue and are equally ambiguous without datum information.

The final entry, with seventeen digits of precision, suggests that either the user is referring to individual atoms in the much-larger-scale whole-Earth coordinate system, or (perhaps more likely) has not bothered to format the values from the GPS module for viewing in the software UI in any way whatsoever, resulting in a value that is [https://en.wikipedia.org/wiki/False_precision meaninglessly precise] because the measurement wasn't that [https://en.wikipedia.org/wiki/Accuracy_and_precision accurate] to begin with. Even if the value is accurate, locating individual atoms by coordinates is not actually useful in most cases, and the motions of multiple systems within our physical world (continental drift, subtle vibrations, etc.) would render the precise value obsolete rather quickly.

For the decimal places past the 5th on the latitude, the digits given are actually the decimal expansion of the constant ''e'' (2.7182818284), while for the decimal places past the 6th on the longitude, the digits given are the decimal expansion of the constant ''pi'' (3.14159265358).

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Single panel containing a table with two columns for "Lat/Lon Precision" and "Meaning" and a caption above the table.]
:Caption: What The Number of Digits in Your Coordinates Means

:[Row 1]
:Lat/Lon: 28°N, 80°W
:Meaning: You're probably doing something space-related

:[Row 2]
:Lat/Lon: 28.5°N, 80.6°W
:Meaning: You're pointing out a specific city

:[Row 3]
:Lat/Lon: 28.52°N, 80.68°W
:Meaning: You're pointing out a neighborhood

:[Row 4]
:Lat/Lon: 28.523°N, 80.683°W
:Meaning: You're pointing out a specific suburban cul-de-sac

:[Row 5]
:Lat/Lon: 28.5234°N, 80.6830°W
:Meaning: You're pointing to a particular corner of a house

:[Row 6]
:Lat/Lon: 28.52345°N, 80.68309°W
:Meaning: You're pointing to a specific person in a room, but since you didn't include datum information, we can't tell who

:[Row 7]
:Lat/Lon: 28.5234571°N, 80.6830941°W
:Meaning: You're pointing to Waldo on a page

:[Row 8]
:Lat/Lon: 28.523457182°N, 80.683094159°W
:Meaning: "Hey, check out this specific sand grain!"

:[Row 9]
:Lat/Lon: 28.523457182818284°N, 80.683094159265358°W
:Meaning: Either you're handing out raw floating point variables, or you've built a database to track individual atoms. In either case, please stop.

{{comic discussion}}

Talk:2168: Reading in the Original

2019-06-26T16:08:41Z

172.68.189.175: pendantic note about ξκσδ transliteration

I removed this line from the explanation: "The New Testament is often studied in the 'original' Greek, despite most of the protagonists actually speaking Aramaic." Reason: While the "protagonists" likely spoke Aramaic, the actual written text was in Koine Greek. The spoken language is a red herring in this case. [[Special:Contributions/162.158.126.118|162.158.126.118]] 14:34, 26 June 2019 (UTC)

There's also a [https://la.wikipedia.org/wiki/Vicipaedia:Pagina_prima Latin Wikipedia] and an [https://ang.wikipedia.org/wiki/H%C4%93afodtramet Old English Wikipedia]. [[User:KangaroOS|Kangaro]][[User talk:KangaroOS|OS]] 14:53, 26 June 2019 (UTC)
:There would have been an Ancient Greek Wikipedia too if not for Yaroslav Zolotaryov and Siberian - [https://meta.wikimedia.org/wiki/Requests_for_new_languages/Wikipedia_Ancient_Greek_2 the proposal] was effectively accepted, and only a little bit short of fulfillment, when the Siberian debacle had Wikimedia revise their acceptance system in October 2007. Alas, despite several re-proposals, there is no Ancient Greek Wikipedia to this day, and realistically there would probably only be one if someone raises a child as an Ancient Greek native speaker. (This had happened with Coptic.) [[Special:Contributions/162.158.182.148|162.158.182.148]] 15:47, 26 June 2019 (UTC)

Btw there's no Greek Wikipedia page for Xkcd :) [[Special:Contributions/172.68.51.166|172.68.51.166]] 14:58, 26 June 2019 (UTC)
:Well, it would rather be for χκcδ [[Special:Contributions/198.41.230.112|198.41.230.112]] 15:44, 26 June 2019 (UTC)
::Rather ξκcδ/ξκσδ as xi (not chi) is equivalent to 'x'. The lunate sigma is rather uncommon. Of course I think if we're talking about ancient Greek there were no lowercase letters so it'd be ΞΚΣΔ. [[Special:Contributions/172.68.189.175|172.68.189.175]] 16:08, 26 June 2019 (UTC)

1649: Pipelines

2017-10-26T20:16:30Z

172.68.189.175:

{{comic
| number = 1649
| date = February 29, 2016
| title = Pipelines
| before = [[#Explanation|↓ Skip to explanation ↓]]
| image = pipelines.png
| titletext = In the future, every single pipeline will lead to the bowl of a giant blender, and we'll all just show up with a bucket each day to take our share of the resulting smoothie.
}}

==Explanation==
{{incomplete|The table with all the items should be filled out with explanations etc. and the diameter should be calculated from real data (with references). Or with the new version of the table another column should be added with the use in gigaliter for each substance in the US to compare. Anyone who is up for calculating how long it would take to fill the pool with US saliva?}}

This comic follows a similar idea to the [[what if?]] ''{{what if|147|Niagara Straw}}'' from three days before this comic's release, where the entire water flow over {{w|Niagara Falls}} is imagined to be funneled through a straw (i.e. 7 mm diameter), with disastrous results.

In this comic [[Randall]] imagines what size pipes are necessary to carry US domestic production/consumption of various fluids if the flow rate were fixed at 4 meters per second. Randall notes that "many pipes would overlap", owing to the fact that consumption of one item as corn syrup would be due to the production of one of the others, in this case soda pop (another example, than the previous one which is actually mentioned in the comic, could be gasoline which is produced from petroleum ).

The top panel is in [http://store-xkcd-com.myshopify.com/products/actual-size-stickers actual size] (something Randall often jokes about, like in the very next released what if? ''{{what if|148|Eat the Sun}}'', where he shows part of the sun in actual size in the 2nd picture, but in this comic he ''actually'' means it). This means that if you look at the image in actual size (or measure lengths in the full size image) then the measured diameter is the diameter Randall has calculated the pipe should be, based on his data for the consumption of these substances.

In the second panel the pipes are too big for his drawing. To indicate the scale he has both inserted a woman ([[Blondie]],) and the top panel has been shrunk down to indicate how much larger the bottom panel is (this is similar to the link between the panels in [[980: Money]]). Using the size of the top panel and the smaller insert, it can be found that the scale is 20:1. The woman is 9 cm tall in the image, which makes her 180 cm — 5 feet 11 inches — in "real life". The pipe next to her for gasoline would have a diameter of 2.2 m.

Since the caption at the top mentions both fluid produced and consumed in the US it becomes very difficult to find out which number Randall uses. For instance the consumption of wine in the US and the production of wine in the US is not necessarily the same as wine is both imported and exported. Should there then be two pipes? Unlike similar comics (like Money mentioned above) there are no references for where Randall has the data for this comic.

As usual with xkcd, the absurdity — and improbability — of routing the entirety of each fluid through a single pipe at any point is the source of humor. In addition, despite Randall's stated assumption that all the fluids are magically flowing at the same rate as public water (4 meters per second), many could never actually do so; some "fluids" shown are too viscous (e.g. peanut butter, Silly Putty, meat), adhesive (e.g. maple syrup), or thermally impractical (e.g. glass, cheese, ice cream and yogurt). Lastly, many are just plain zany (e.g. saliva a reference to another what if? {{what if|144|Saliva Pool}}). Note that at the bottom of the last panel there is a much larger pipe for the tap water used by the public. All substances are listed below in the [[#Table|table]].

The title text refers to a possible future based on the idea of this comic in which all the pipes with the above-mentioned fluids will actually lead into the same hole as shown in the top right panel. This hole will then be the bowl of a giant blender that mixes all these substances together to a ''{{w|smoothie}}''. The future people will then just come up to this blender and get a bucket full of this mix each day. In reality, this would be an impractical method of getting all of the fluids. Setting the logistical considerations of such a setup aside, this would mean that ketchup and salsa, both intended for human consumption, would be mixed with fluids which are harmful to humans, such as windshield wiper fluid.

Note: "Soup" has been left out, and it might have been expected in this comic due to the similarity to this system with [[Beret Guy]]'s use of a "soup outlet" as an entrepreneur in [[1293: Job Interview]]. It is probably a larger pipeline than salsa and possibly even ketchup. However, there are many different varieties of soups, and most soup is probably not bought finished, both very good reasons to not include it in the chart. But still the idea of having a soup outlet is very similar to this comic.

===Table===
*All the substances are listed here in the "reading" order also used in the transcript.
*The diameter is for the inner part of the tube.
*GL is for GigaLiters - or Billion Liters. This is strictly the annual discharge of the Size (cm) column at 4 m/s.
{| class="wikitable sortable"
|-
|+ All substances with size as found in the picture, vs. size calculated from public information
|-
! scope="col" | Substance
! scope="col" | Size (cm)
! scope="col" | Annual Discharge (GL)
! scope="col" | Explanation
|-
| {{w|Toothpaste}}
| 3.5
| 0.121
| In the title text of [[1599: Water Delivery]] Randall claims that he as a child could not understand why there were no toothpaste pipe to his house when there was one for water. Given this is at the top, this is a clear allusion to this comment. Calculation is based on 542 g/year per capita consumption of toothpaste. Source:[https://www.google.com/search?q=toothpaste+consumption+by+country&tbm=isch&pf=m#imgrc=2wpGcxkoKlCvAM%3A here].
The year the graph was made in is estimated to be 2013, and 316.5 million estimated 2013 US population to calculate the diameter above.
|-
| {{w|Nail polish}}
| 0.4
| 0.000159
| Much less than acetone, which is used as a nail polish remover.
|-
| {{w|Windshield washer fluid}}
| 5.6
| 0.311
| Largely water
|-
| {{w|Silly putty}}
| 0.1
| 0.0000991
| Smallest diameter
|-
| {{w|Shampoo}}
| 4
| 0.159
| As most people wash hopefully every few days this would be a larger pipe.
|-
| {{w|Honey}}
| 5.2
| 0.268
|In both pure form and many honey products.
|-
| {{w|Blood donation|Donated blood}}
| 0.9
| 0.00803
| A small pipe as not many operations need a huge blood transfer.
|-
| {{w|Vanilla}}
| 0.4
| 0.000159
| Not the ice but the spice (which is black as the substance in the vanilla pipe).
|-
| {{w|Ketchup}}
| 5.2
| 0.268
| A huge ingredient in many products in the U.S. for example McDonalds
|-
| {{w|Salsa (sauce)|Salsa}}
| 3.6
| 0.128
| Smaller than a typical jar
|-
| {{w|Sunscreen}}
| 1.35
| 0.0181
| A smaller pipe that is largely dependent on the season
|-
| {{w|Personal lubricant}}
| 0.65
| 0.00419
| AKA "lube" (sexual lubricant)
|-
| {{w|LCD liquid}}
| 0.26
| 0.000670
| For {{w|Liquid-crystal display}}
|-
| {{w|Mayonnaise|Mayo}}
| 4.4
| 0.192
| Or mayonnaise
|-
| {{w|Printer ink}}
| 1.4
| 0.192
|Some offices and printing centres may need a medium size pipeline of ink.
|-
| {{w|Maple syrup}}
| 1.8
| 0.0178
| Used as a topping on pancakes. As it is a relatively popular ingredient it has a medium sized pipe
|-
| {{w|Hair conditioner|Conditioner}}
| 2.5
| 0.0620
| For hair
|-
| {{w|Mustard (condiment)|Mustard}}
| 3.7
| 0.136
| Like with ketchup popular topping but not so much.
|-
| {{w|Liquid soap}}
| 4.7
| 0.219
| A large pipeline as many people use this.
|-
| {{w|Olive oil}}
| 6.2
| 0.381
| Largest diameter in the upper chart
|-
| {{w|Coffee}}
| 58
| 33.4
| Extremely popular drink in the U.S. as many people drink it in the morning so it has a medium sized pipeline in the upper chart
|-
| {{w|Peanut butter}}
| 8.6
| 0.733
| Smallest diameter in the bottom chart
|-
| {{w|Ice cream}}
| 20
| 3.97
| Most likely solid rather than melted. This would be a weird pipe as the ice cream would have to be melted to be transported through the pipe and then refrozen to a blend of all flavours. Then again, if the future was really the scenario in the title text then mixing flavours isn't so bad.
|-
| {{w|Cheese}}
| 70
| 48.6
| Made from milk (cow) also in the chart
|-
| {{w|Soft Drink|Soda}}
| 82
| 66.7
| As in {{w|Soft Drink|soda pop}} aka soft drinks (flavored carbonated water) or {{w|Carbonated water|club soda}} (unflavored carbonated water). In many parts of the U.S. flavored carbonated water is referred to simply as "soda".
|-
| {{w|Acetone}}
| 13.6
| 1.83
| An organic chemical used as a highly potent cleaner in labs.
|-
| {{w|Liquor}}
| 15
| 2.23
| May not include beer or wine (also in chart)
|-
| {{w|Gasoline}}
| 220
| 480.
| Made from petroleum, also in the chart
|-
| {{w|Yogurt}}
| 15
| 2.23
| Made from milk (cow), also in the chart
|-
| {{w|Milk#Cow.27s_milk|Milk (cow)}}
| 106
| 111
| All the milk that comes from cows. A large pipeline
|-
| {{w|Bottled water}}
| 71
| 50.0
| See also [[1599: Water Delivery]]
|-
| {{w|Sugar}}
| 42
| 17.5
| See also [[1639: To Taste]]
|-
| {{w|Saliva}}
| 85
| 71.6
| From this data it could be calculated how long it would take America to drool enough to fill that pool from the what if? {{what if|144|Saliva Pool}}.
|-
| {{w|Wine}}
| 18
| 3.21
| Americans drank just under [https://www.wineinstitute.org/resources/statistics/article86 900 million gallons of wine in 2014], or almost 3.4 million cubic metres per year meaning that Americans drink about 0.11 m3/s. With the pipe flowing at 4 m/s this | pipe must have an area of 268 cm2. The radius of a pipe of area 268 cm^2 is 9.25 cm. The wine pipe should thus | have a diameter of 18.5 cm, very close to the one found by measuring on the chart.
|-
| {{w|HFCS}}
| 20
| 3.97
| High fructose corn syrup is a wildly used sweetener, mostly found in soft drinks. It is naturally found in a low concentration in most fruits (sucrose is made out of a glucose molecule bonded to a fructose molecule), and thus it can be naturally extracted from corn.
|-
| {{w|Breast milk|Milk (human)}}
| 10.6
| 1.114
| A rather small pipe as many people do not breastfeed.
|-
| {{w|Petroleum}}
| 318
| 1002
| Largest diameter in the bottom chart, except for the public water. Also known as crude oil. Used to make for instance gasoline, also in the chart.
|-
| {{w|Meat}}
| 59
| 34.5
| The amount of meat purchased in the U.S. This "pipeline" would be mostly solid save for some blood.
|-
| {{w|Glass}}
| 28
| 7.77
|Glass is rumored to be a liquid. However, glass is an amorphous solid; people, wrongfully, assume this lack of crystalline structure gives it the potential for viscous flow, making it technically a liquid (non-newtonian). This is incorrect as glass is composed of covalently bound molecules in a somewhat disorganized fashion, more similar to a thermoset plastic than a liquid. This common misconception was referred to before in the title text of [[843: Misconceptions]].
|-
| {{w|Beer}}
| 54
| 28.9
| As only people over 21 can buy this it is a smaller pipe.
|-
| {{w|Tea}}
| 41
| 16.67
| Smaller than coffee as many people prefer coffee but some like tea more.
|-
| {{w|Cement}}
| 74
| 54.3
| As most buildings have this and there are countless construction projects ongoing this is a large pipe.
|-
| {{w|Tap water|Public water}}
| 2550
| 64,465
| Using the formula [http://math.stackexchange.com/questions/564058/calculate-the-radius-of-a-circle-given-the-chord-length-and-height-of-a-segment here] it is possible to calculate the diameter of a circle given the chord length = l and height = h of a segment. From the drawing (and scaling) l = 390 cm and h = 15 cm. The formula states that D = h + l2/(4*h) = 15 cm + (390 cm)2/(4*15 cm) = 2550 cm.
|}

==Transcript==
:[Caption above the first main panel, to the left of a smaller panel to the right.]
:<big>The size of the US’s</big>
:<big><big>'''Pipelines'''</big></big>
:<big>if each fluid produced or consumed in the US has to be carried by a single pipe</big>
:Assuming they all flowed at the same speed of about 4m/s
:Note: Many pipelines would overlap (eg. '''soda'''/corn syrup)

:[There is a small panel to the right showing three gray pipes of different sizes leading out over a large hole in the ground. Only a part of the hole can be seen at the bottom left part of the panel, but it curves around indicating it is a large circular hole. The pipes are supported by small legs beneath them and from the end of all three thick liquids are squirting out and down into the hole. The first pipe is by far the largest; the liquid from it is white, but not as white as the background. The second pipe is by far the smallest squirting dark red liquid and the final rightmost pipe is in between and squirts our light brown liquid. Each pipe is labeled. The label on the smallest cannot be read properly, but from the info gained in the next panel it can be inferred for certain what it says (and this is indicated here below):]
:[Large pipe (white)]: Mayo
:[Small pipe (dark red)]: Nail polish
:[Medium pipe (light brown)]: Maple syrup

:[Below is a large panel with a caption at the top. And below this there are twenty circles in different sizes and with different color (or even texture). Each circle is labeled, for the five smallest the label is outside, in one case with an arrow indicating where the label belongs. The rest has the label inside. The text is in black except for four of those with text inside, but with red of black color. Here the text is white. The labels are indicated by color and size, going roughly from top left in reading order based on the position and size of circles not of position of the text:]

:<big>Actual size </big> (When viewed on a typical computer screen) 
:[Medium green blue and white spiral]: Toothpaste
:[Tiny dark red]: Nail polish
:[Big light blue with white specks]: Windshield washer fluid
:[Very tiny purple]: Silly putty
:[Medium light green]: Shampoo
:[Large dark yellow]: Honey
:[Very small blood red]: Donated blood
:[Tiny black]: Vanilla
:[Big red]: Ketchup
:[Medium dark red with chunks of in different green and lighter red colors]: Salsa
:[Small white]: Sunscreen
:[Very small light green]: Personal lubricant
:[Very tiny gray]: LCD liquid
:[Medium off-white]: Mayo
:[Very small black]: Printer ink
:[Small light brown]: Maple syrup
:[Small light green]: Conditioner
:[Medium yellow]: Mustard
:[Large light green]: Liquid soap
:[Big olive green]: Olive oil

:[The panel just described is indicated to fit into a small rectangle at the top left of the next panel below. There are four lines ending at the four corners of this small rectangle, two of these are going to the two bottom corners and the other two ends on the lower part of the panel just above the small rectangle. They are indicated to go under the panel and would hit the two top corners if extrapolated. The 11 largest circles are clearly seen, but most of the other circles can also be noted. The colors are the same but any features in the original circles as well as the labels are gone. The part of the black top frame of the next panel below is faded out to gray in between the section cut off by the two lines going to the bottom corners of the panel above. This rectangle indicated the increasing size compared to the first panel above.]

:[Apart from the insert mentioned above the second panel follows the same layout, but with 22 circles with even larger range of sizes. The panel is more than twice as long as the first panel. Blondie is drawn at the top of the panel just left of the middle. Her hair close to the top, just below the line going to the right corner above. There are two medium and five smaller circles to her left and one small close to her head and one huge circle to her right. Her feet are less than a third down this panel standing on top of the next row of circles. In the bottom half of the panel there is a giant circle which almost touches the left side of the panel. There are smaller circles above it and down along the right side. One last circle is to the left almost at the bottom. At the very bottom is a slightly curving line to indicate a much much larger blue circle that only graces the panel (no. 23). There is a small green fish in this water to the left of the label. Below the labels are again listed as above. One label has a foot note. But it is written directly beneath the circle in which it is referenced. So it will be written together with the label on the next line. There is also one case with an arrow used to indicate where the label belongs.]

:[Medium dark gray]: Coffee
:[Very tiny gray]: Peanut butter
:[Very small gray with black specks]: Ice cream
:[Very small yellow with white specks]: Cheese
:[Large brown with white fizzing]: Soda
:[Tiny White]: Acetone
:[Tiny gray]: Liquor
:[Huge dark yellow]: Gasoline
:[Tiny White with blue and orange specks]: Yogurt
:[Big white]: Milk (cow)
:[Large light blue]: Bottled water
:[Small white]: Sugar
:[Large light gray with white specks]: Saliva
:[Very small light yellow]: Wine
:[Very small orange]: HFCS
:[Very tiny white]: Milk (human)
:[Gigantic dark gray]: Petroleum
:[Medium dark red with black texture]: Meat (mostly solid)
:[Small white]: Glass*
::<nowiki>*</nowiki>Solid at room temperature
:[Medium light brown]: Beer
:[Small gray brown]: Tea
:[Large gray]: Cement
:[Gracing bottom of panel light blue, with a fish inside]: Public water

==Trivia==
*In addition to the what if? article, the relevancy of pipelines, particularly regarding public water, is heightened due to the ongoing public health crisis in {{w|Flint, Michigan}}, caused by recent (mis-)management of their public water system.
**See McLaughlin, Elliot. [http://edition.cnn.com/2016/01/18/us/flint-michigan-water-crisis-five-things/index.html 5 things to know about Flint's water crisis], '{{w|CNN}}', January 21, 2016. Retrieved 1 March 2016.
**Studies have shown that temporary use of the Flint River as a water source caused corrosive water to leach lead from old pipes, causing lead poisoning in many residents, particularly children; other ill effects in addition to lead have been noted.
**The crisis has lead to a public outcry against the state "emergency financial management" team appointed and supervised by the state executive (Gov. Rick Snyder and staff) and an outpouring of support from nearby communities such as Metro Detroit via bottled water donations to Flint residents.
*This is the third comic posted on Leap Day ({{w|February 29}}) on Monday in 2016; the previous ones were:
**[[390: Nightmares]] on a Friday in 2008 and
**[[1023: Late-Night PBS]] on a Wednesday in 2012.
**If the current M-W-F schedule continues, the next such comic will not happen before 2036 when the leap day again falls on a Friday (Following the {{w|Solar cycle (calendar)|28 year cycle}}).
**It may also be interesting to note that the first three leap years after xkcd began (in just over 10 years) all fell on a release day, then followed by a break of 20 years.

{{comic discussion}}

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