explain xkcd - User contributions [en]

1484: Apollo Speeches

2015-02-09T06:37:00Z

199.27.128.86: Quick explanation, but it will need to be built on. A bunch. Hope this is good enough for you to work with, whoever you are.

{{comic
| number = 1484
| date = February 9, 2015
| title = Apollo Speeches
| image = apollo_speeches.png
| titletext = While our commitment to recycling initiatives has been unwavering, this is not a cost any of us should be expected to pay.
}}

==Explanation==
{{incomplete|The framework is laid out. Needs a much more in-depth explanation, however.}}As explained in the comic, Nixon Staffer William Safire wrote two speeches for the United States President to deliver depending on whether or not the Apollo 11 return launch was successful. The reason for two different speeches having been written was that the return launch had an outcome that could not be predicted with certainty. Such an uncertain event could be called a contingency, making the speeches "contingency speeches".

The rest of the comic runs with this theme, making the false claim that Safire had written several other such contingency speeches for increasingly unlikely possibilities. First listed is the speech to be delivered in the event that the astronauts were left stranded on the moon. Laying on top of that is a speech to be delivered in the case that the spacecraft goes missing altogether, which is relatively unlikely. The speeches after that deal with the following contingencies: the astronauts had stolen the ship and piloted it to Mars; upon landing, more astronauts were found in the ship; the ship had hit the U.S.S. Hornet and crushed Nixon; and the ship had been sold for scrap and crushed along with the astronauts inside.

The title text builds upon this last contingency speech, delving into the irony of the horror of the spacecraft's recycling and its passengers resulting deaths despite the U.S.'s commitment to recycling initiatives.

==Transcript==
{{incomplete transcript}}

{{comic discussion}}

1461: Payloads

2014-12-17T19:29:13Z

199.27.128.86: /* Tables */ Minor corrections

{{comic
| number = 1461
| date = December 17, 2014
| title = Payloads
| image = payloads.png
| titletext = With a space elevator, a backyard full of solar panels could launch about 500 horses per year, and a large power plant could launch 10 horses per minute.
}}

A larger version of the image can be found [http://imgs.xkcd.com/comics/payloads_large.png here].

==Explanation==
{{incomplete|Discuss space elevator aspect from title text, touch on horsepower vs [[rocket equation]], thrust, specific impulse, payload to orbit. E.g., compare with question of a horse getting itself into orbit?}}
This comic lists the payload capacity of several launch vehicles, and the mass of several spacecraft, in number of horses. This could be related to Randall's hobby of abusing dimensional analysis, as horses/ship is technically a perfectly acceptable derived unit, provided the size of a horse is standard (in this comic it appears that 'one horse' is defined as 450 kg). In cases where the mass is less than one horse, an alternative measure of dogs has been used, where one dog appears to be roughly 40 kg. In the case of {{w|Vanguard 1}}, even a dog is too large a measure, so instead the unit squirrel is used to represent its 1.47 kg mass.

The overall comic is an allusion to {{w|horsepower}}, a similar-sounding but completely different concept. Horsepower is a measurement of {{w|power (physics)|power}} ({{w|work (physics)|work}} per unit time). Another commonly referenced unit for power is the {{w|watt}}. 1 horsepower is meant to be approximately the amount of power a horse can deliver. In contrast, Randall uses the horse to measure {{w|mass}} (of spacecraft themselves, and of the payload they carry).

The top pane of the comic shows the mass of various spacecraft, while the bottom shows the amount of mass they can deliver to {{w|low earth orbit}}. There are also several joke insertions. In the top, one is T-Rex. In the bottom, another is Pegasus (the payload capacity given as one Pegasus); this is a reference to both Pegasus {{w|Pegasus (rocket)|the rocket}} and Pegasus the {{w|Pegasus|mythical flying stallion}}. Atlas-Centaur is also measured in centaurs, a reference to the half-human half-horse creatures of Greek mythology. The bottom also gives the 1981 {{w|Oldsmobile}} as 4 horses; presumably, this is actually the number of horses the Oldsmobile could tow, rather than launch into low earth orbit.

The Pegasus, 1981 Oldsmobile, and Stratolaunch spacecraft are depicted horizontally, presumably because these vehicles launch from a horizontal starting position and use forward momentum to facilitate their launch.

There is an unlabeled launch vehicle below the H-11A near 2002. The unlabeled vehicle has a playload mass of 21 horses (9450 kg).

===Tables===
The tables below contain data relating to each entry on the comic image.

*Name - Should be as shown in the comic
*Launch Date - Date of first flight
*Mass/Payload (Horses) - Value as given in comic
*Mass/Payload (kg) - Independently researched value

{|
|- style="vertical-align:top;"
|

{| class="wikitable sortable"
!colspan="4"|Spacecraft Mass
|-
!Spacecraft
!Launch Date <sup>''{{w|ISO 8601}}''</sup>
!Mass (Horses)
!Mass (kg)
|-
|{{w|Sputnik 1|Sputnik}}
|1957-10-04
|2 Dogs
|83.6
|-
|{{w|Vanguard 1}}
|1958-03-17
|Squirrel
|1.47
|-
|{{w|Pioneer 5}}
|1960-03-11
|Large Dog
|43
|-
|{{w|Venera 1}}
|1961-02-12
|1
|643.5
|-
|{{w|Mariner 2}}
|1962-08-27
|3 Dogs
|202.8
|-
|Apollo
|
|67
|
|-
|{{w|Venera 7}}
|1970-08-17
|3
|1,180
|-
|{{w|Pioneer 10}}
|1972-03-03
|7 Dogs
|258.8
|-
|{{w|Skylab}}
|1973-05-14
|171
|77,088
|-
|{{w|Venera 9}}
|1975-06-08
|11
|4,936
|-
|{{w|Voyager 2}}
|1977-08-20
|2
|721.9
|-
|Shuttle (Total)
|
|206
|
|-
|Shuttle (Payload)
|
|54
|
|-
|{{w|Mir}}
|1986-02-20
|288
|129,700
|-
|T-Rex
|
|15
|6,800
|-
|{{w|Hubble}}
|1990-04-24
|25
|11,110
|-
|{{w|Compton Gamma Ray Observatory}}
|1991-04-05
|38
|17,000
|-
|{{w|Corona (Satellite)|Keyhole 3}}
|
|40
|
|-
|{{w|International Space Station}}
|1998
|932
|450,000
|-
|{{w|Cassini-Huygens|Cassini}}
|1997-10-15
|11
|5,300
|-
|{{w|Huygens (spacecraft)|Huygens Lander}}
|1997-10-15
|1
|319
|-
|{{w|Rosetta (spacecraft)|Rosetta}}
|2004-03-02
|6
|2,900
|-
|{{w|Opportunity (rover)|Opportunity}}
|2003-07-07
|5 Dogs
|185
|-
|{{w|Dawn (spacecraft)|Dawn}}
|2007-09-27
|3
|1,240
|-
|{{w|TerreStar-1|Terrastar}}*
|2009-07-01
|15
|6,910
|-
|{{w|Dragon (spacecraft)|Dragon}}
|2010-12-08
|17
|
|-
|{{w|Tiangong-1}}
|2011-09-29
|19
|8,506
|-
|{{w|Curiosity (rover)|Curiosity}}
|2011-11-26
|2
|900
|-
|{{w|Corona (Satellite)|Keyhole 7}}
|
|40
|
|-
|{{w|Orion (spacecraft)|Orion (Capsule)}}
|2014-12-05
|20
|8,913
|-
|{{w|James Webb Space Telescope|James Webb Telescope}}
|
|14
|6,200
|-
|{{w|Orion (spacecraft)|Orion}}
|2014-12-05
|20
|8,913
|-
|{{w|Orion Service Module}}
|
|25
|12,000
|-
|{{w|Deep Space Habitat|Orion Deep Space Habitat}}
|
|65
|
|}

Terrastar is believed to be a mis-spelling of {{w|TerreStar-1|TerreStar}}, based on its mass and launch date.

|

{| class="wikitable sortable"
!colspan="4"|Lauch Vehicle Capacity
|-
!Spacecraft
!Launch Date <sup>''{{w|ISO 8601}}''</sup>
!Payload (Horses)
!Payload (kg)
|-
|{{w|Sputnik (rocket)|Sputnik Launcher}}
|1957-10-04
|1
|500
|-
|{{w|Thor-Able|Thor}}
|1958-04-24
|3 Dogs
|120
|-
|{{w|Mercury-Atlas}}
|1960-07-29
|3
|1,360
|-
|{{w|Saturn I}}
|1961-10-27
|20
|9,070
|-
|{{w|Proton-K}}
|1967-03-10
|44
|
|-
|{{w|Atlas-Centaur}}
|1962-05-08
|8 Centaurs
|
|-
|{{w|Titan IIIA}}
|1964-09-01
|7
|3,100
|-
|{{w|Saturn IB}}
|1966-02-26
|45
|21,000
|-
|{{w|Soyuz (rocket)|Soyuz}}
|1966-11-28
|14
|6,450
|-
|{{w|Saturn V}}
|1967-11-09
|262
|118,000
|-
|{{w|Black Arrow}}
|1969-06-27
|4 Dogs
|135
|-
|{{w|N1 (rocket)|N1}}
|1969-02-21
|211
|90,000*
|-
|{{w|Long March 1}}
|1969-11-16
|2
|300*
|-
|{{w|N-I (rocket)|N-I}}
|1975-09-09
|4
|1,200*
|-
|{{w|Delta 0100|Delta 0900}}
|1972-07-23
|3
|1,300
|-
|{{w|Ariane 1}}
|1979-12-24
|3
|1,400
|-
|{{w|Satellite Launch Vehicle|SLV}}
|1979-08-10
|1 Dog
|40
|-
|{{w|N-II (rocket)|N-II}}
|1981-02-11
|4
|2,000
|-
|{{w|Oldsmobile#1970s-1980s|1981 Oldsmobile}}
|1981
|4
|
|-
|{{w|ASLV}}
|1987-03-24
|4 Dogs
|150
|-
|{{w|Long March 4A}}
|1988-09-06
|9
|4,000
|-
|{{w|Ariane 4}}
|1988-06-15
|16
|5,000-7,600*
|-
|{{w|Shavit}}
|1988-09-19
|6 Dogs
|350-800*
|-
|{{w|Energia}}
|1987-05-15
|218
|100,000*
|-
|{{w|Pegasus (rocket)|Pegasus}}
|1990-04-05
|1 Pegasus
|443
|-
|{{w|Atlas I}}
|
|13
|
|-
|{{w|PSLV}}
|
|8
|
|-
|{{w|J-I}}
|
|2
|
|-
|{{w|Long March 3B}}
|
|27
|
|-
|{{w|H-IIA}}
|
|22
|
|-
|(unlabelled) {{w|Delta IV#Delta IV Medium|Delta IV M}}?
|
|21
|
|-
|{{w|Delta IV Heavy|Delta IV-H}}
|
|64
|
|-
|{{w|Falcon 1}}
|
|1
|
|-
|{{w|Ariane 5#Variants|Ariane 5ES}}
|
|47
|
|-
|{{w|H-IIB}}
|
|37
|
|-
|{{w|UNHA}}
|
|2 Dogs
|
|-
|{{w|Atlas V|Atlas V 541}}
|
|38
|
|-
|{{w|Falcon 9}}
|
|29
|
|-
|{{w|Antares (rocket)|Antares}}
|
|14
|
|-
|{{w|Stratolaunch}}
|
|14
|
|-
|{{w|Falcon Heavy}}
|
|118
|
|-
|{{w|Space Launch System|SLS Block 1}}
|
|156
|
|-
|{{w|Space Launch System|SLS Block 1B}}
|
|217
|
|-
|{{w|Space Launch System|SLS Block 2}}
|
|289
|
|}

|}

==Transcript==
{{incomplete transcript}}

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Animals]]
[[Category:Space]]

Talk:1422: My Phone is Dying

2014-09-17T08:42:50Z

199.27.128.86:

The dying of Beret's phone is similar to the dying of the sun.

The Sun does not have enough mass to explode as a supernova. Instead it will exit the main sequence in approximately 5.4 billion years and start to turn into a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of the solar system's inner planets, possibly including Earth. (via http://en.wikipedia.org/wiki/Sun) [[User:Oicebot|Oicebot]] ([[User talk:Oicebot|talk]]) 04:43, 17 September 2014 (UTC)

I thought, this might be a TARDIS reference. --[[Special:Contributions/141.101.93.210|141.101.93.210]] 07:03, 17 September 2014 (UTC)

----

The main page of this explanation mentions White Hat... he's not even in this comic, only Beret Guy and Cueball. Not sure about editing policies/things here yet, so figured I'd mention this on the talk page :P Hope this helps! [[User:Tanos|Tanos]] ([[User talk:Tanos|talk]]) 06:43, 17 September 2014 (UTC)

----

Reference to the iPhone (and may be other smartphones) which becomes bigger and bigger with every release. At the same time iPhone becomes less popular and it is 'dying' this way. So - the bigger iPhone becomes the closer it is to 'death'. And it was like a star among other smartphones.
In the title text it may be a jesting prophesy - one on future generation of iPhone will be like a set of some separate devices.

[[Special:Contributions/108.162.246.229|108.162.246.229]] 07:42, 17 September 2014 (UTC)

----

The first paragraph assumes that the phone is going to become a white dwarf and the supernova is not mentioned until lower down. Personally, I read the "collapse in a violent explosion" comment from the fourth panel as implying that it was already on its way to becoming a supernova(-analog) and the charger would speed it up. Unless red dwarfs actually explode and leave white dwarfs (which I didn't think they did, but maybe I'm wrong there) concluding that it's analogous to the white dwarf doesn't make sense to me, at least. Thoughts? [[Special:Contributions/199.27.128.86|199.27.128.86]] 08:42, 17 September 2014 (UTC)

1416: Pixels

2014-09-03T09:30:32Z

199.27.128.86: /* Transcript */ It says scroll to zoom, not scroll to 200m.

{{comic
| number = 1416
| date = September 3, 2014
| title = Pixels
| image = pixels.png
| titletext = It's turtles all the way down.
}}
'''NOTE: The above is only a zoomed out version of the this interactive comic.''' For a collection of images that appear when zooming in on this comic, see [[1416: Pixels/Images]].

==Explanation==
{{incomplete|add "gallery" of all zoomed in images}}

When the cursor is placed inside the field of the comic and the viewer scrolls down, the picture zooms in until the pixels are visible. Each pixel then resolves into another comic, with black-on-white comic panels making up the white spaces and white-on-black panels making up the black spaces. This is repeated for this and all subsequent sets of comic panels. Not all white and all black panels are the same; some sets involve more than two different panels, but all involve repetitive tiling. The first comic panel, of Cueball stacking turtles, is a reference to the idiom "turtles all the way down," which refers to the problem of infinite regression: if everything in the universe is "on top of" something else, so to speak, there must be a "bottom." A joking solution to the paradoxical nature of such a bottom is the proposition that [http://en.wikipedia.org/wiki/Turtles_all_the_way_down the world rests on a semi-infinite stack of turtles].

==Transcript==
:[Cueball is stacking turtles, and is about to put the fourth turtle on his pile. At the bottom right there is a small panel. Inside this is written:]
:Scroll to zoom

:[When zooming in there will be several panels with text. The transcript of these may not be possible to complete - but add the transcript of these panels here: [[1416: Pixels/Transcript|interactive transcript]]]

==Bugs==
Doesn't seem to work properly in all browsers (e.g. Firefox and Safari on MacOSX), giving "TypeError: this.data is null" in line 173 of zoom.js: "var item = this.data.get(dims)"
Doesn't seem to work in IE8, comic is blank, but title text works.

Does not work on xkcd.org neither www.xkcd.org in Firefox and Chrome. Currently you should visit http://xkcd.com for this comic to work properly.

There is a bug/type, where there is a chance of white pixels zoom into a missing panel, resulting in a white screen.
This is affecting several panels: "du" (1-in-13), "server-1" (1-in-13), and "time-turner" (1-in-14).
In each case the missing (404) tile is "what-if-trade" (probably should be "whatif-trade")

==Gallery==
Here on the link can be found a [[1416: Pixels/Images|gallery]] with some of the many images found in this extensive comic.

{{comic discussion}}
[[Category:Dynamic comics]]
[[Category:Comics featuring Cueball]]

133: The Raven

2014-07-05T07:49:12Z

199.27.128.86: Added a reference to MC Lars' rap 'Mr Raven' based on the poem.

{{comic
| number = 133
| date = July 26, 2006
| title = The Raven
| image = the_raven.jpg
| titletext = Yes, Eminem is wearing a sleeveless hoodie. What of it?
}}

==Explanation==
The comic's title is a reference to the well-known poem {{w|The Raven}} by {{w|Edgar Allan Poe}}, one of the most popular pieces of poetry in the English language. The comic quotes the first eight lines of the work, in which the {{w|poetic persona}} perceives a strange knocking on his door in the middle of the night. Unlike the original, the comic reveals the nocturnal visitor to be the rapper {{w|Eminem}}.

This unexpected turn reflects the ambiguity of the verb "to rap" in English. According to the [http://www.merriam-webster.com/dictionary/rap Merriam-Webster Dictionary], the word was used in the original sense of "to strike" as early as the 14th century. The meaning of the word was later extended to "talking freely and frankly". In this purport, it was especially employed by the {{w|Black rights movement}} during the 1960s (cp. for example the nom de guerre of {{w|H. Rap Brown}}). The {{w|hip-hop}} subculture, which had its roots in the aforementioned movement, finally adopted the term in the sense of "rhythmic speaking or chanting". Today, the word is almost exclusively used with the latter meaning.

It is thus implied that the poetic persona in the comic hears Eminem performing a rap song, rather than someone knocking on the door as in the original. Note also that rap music is usually considered fairly aggressive, which seems to contradict the poem's description of a "gentle" sound.

Beyond a linguistic interpretation of the comic, it may be added that rap music and poetry bear a lot of similarities: Some of the more advanced rap lyrics feature classical {{w|stylistic device|stylistic devices}} like alliterations or inline rhymes as well as a more or less complex metrical structure. The {{w|metre (poetry)|meter}} of a classical poem, on the other hand, gives the piece a distinct, almost musical rhythm, albeit it is not accompanied by any instruments. Nerdcore rapper {{w|MC Lars}} has recorded a rap version of the poem (with some additional lyrics and modern references added) called 'Mr. Raven', which can be heard [https://www.youtube.com/watch?v=d3z4mY5Xvr8 here]. (For a comparison between the verbal capabilities of Edgar Allan Poe and Eminem, see [http://thequietus.com/articles/04918-the-curious-similarities-betwixt-edgar-allan-poe-the-rapper-eminem this article].)

"The Raven" is heavily {{w|The Raven in popular culture|referenced}} in popular culture. Interestingly enough, the webcomic [http://www.qwantz.com/index.php?comic=805 Dinosaur Comics] had a reference to Edgar Allan Poe three weeks before the xkcd comic was published. There is also a [http://www.penny-arcade.com/comic/2011/04/13 Penny Arcade] version of the "Raven" trope.

The title text, besides defending the graphic style of the drawing, also lampshades at the somewhat peculiar taste of fashion found in the hip-hop subculture. In the picture, Eminem wears a sleeveless hoodie. While the aesthetic value of such garment might be disputed, it certainly defeats the purpose of keeping its bearer warm.

==Transcript==
:Once upon a midnight dreary
:While I pondered, weak and weary,
:Over many a quaint and curious
:Volume of forgotten lore
:While i nodded, nearly napping,
:Suddenly there came a tapping
:As if someone gently rapping
:Rapping at my chamber door...
:[A door opens, revealing Eminem wearing a hoodie.]
:''click''
:''creak''
:Eminem: Yo.

{{comic discussion}}
[[Category:Comics featuring real people]]
[[Category:Language]]

1370: President

2014-05-24T07:52:28Z

199.27.128.86: /* Exploring the more philosophical & psychological layers of the comic */

{{comic
| number = 1370
| date = May 19, 2014
| title = President
| image = president.png
| titletext = Anyone who thinks we're all going to spend the 2032 elections poring over rambling blog posts by teenagers has never tried to read a rambling blog post by a teenager.
}}

==Explanation==

This strip shows a discussion between an adult and a teenager about an aspect of the future. [[Randall]] likes this setup, allowing to put in perspective the various "decay" predictions and shows his optimism.

Here, the subject is scandal. How will a generation that is documenting and leaving behind a permanent public record of its juvenile misadventures - immature and impolitic writings, photographs of inebriation at parties posted on Facebook, Twitter posts about breakups, etc. - produce successful future politicians? Won't future opposition researchers and reporters have enough embarrassing material to destroy any Millennial's public reputation? In previous generations, juveniles were freer to go through this phase of development without leaving behind a digital record, making it easier to sidestep or paper over rumors of youthful misbehavior. (See, e.g., George W. Bush, who dismissed questions about his rumored use of drugs in his youth by saying only, "When I was young and stupid, I was young and stupid.")

The child's answer, in addition to tweaking the adult about her generation's coming obsolescence, is that the next generation will be fine because in the future no one will care. The title text amplifies this optimistic message, suggesting that old blog posts by former teenagers will just seem boring, not salacious. [[Randall]] offers no explanation for this upbeat spin, but it is a recurring topic and some have argued elsewhere that the potential power of Internet-chronicled youthful indiscretions will be defused because everyone will be in the same boat, making future voters (and, in another context, employers) more tolerant of such things.

The strip also contains an existential twist, as shown in the child's answer. It alludes to every generation's dismissal of the next, as actually being due to psychological insecurities. We may disguise our dismissals by attacking their faults & different lifestyles. But in truth, these dismissals are actually rooted in our innate fear of becoming obsolete, useless, surpassed, and lost in a bewildering world that has passed us by.

==Transcript==
:[Ponytail and a kid with curly hair are walking together.]
:Ponytail: I can't imagine anyone who grew up on the Internet being able to run for President.

:[Closeup of Curly.]
:Curly: Why? Because it'd mark the handover of a world that no longer needs you to a generation you don't understand?

:[Ponytail and Curly have stopped walking and are facing each other.]
:Curly: ...Or because there would be embarrassing pictures of us as teenagers?

:[Closeup of Ponytail.]
:Ponytail: Um. The pictures one?
:Curly (off-screen): Pictures of teens! How will we even survive??

{{comic discussion}}

[[Category:Comics featuring Ponytail]]
[[Category:Internet]]