explain xkcd - User contributions [en]

Talk:3037: Radon

2025-01-15T21:08:53Z

141.101.98.172:

The sun is a white star. It looks yellow from within the atmosphere because blue light is scattered out of it, the same reason the sky is blue. How did physicist Randall not know that? [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 20:26, 13 January 2025 (UTC)
:Randall is almost certainly a Superman fan, and we all know that Kryptonians get their powers from yellow suns. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:07, 13 January 2025 (UTC)
:Wikipedia disagrees; The Sun is a G-type main-sequence star (G2V), informally called a yellow dwarf, though its light is actually white. It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. [[Special:Contributions/172.71.23.87|172.71.23.87]] 20:43, 13 January 2025 (UTC)
::Your quote agrees with me. As @Starstar says below, it might be intentional on his part. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 20:53, 13 January 2025 (UTC)
::: No "his quote" doesn't?? (Unless I'm understanding your meaning with "his quote") Yes the sun is White. HOWEVER, it is NOT called a "white star". Stars aren't categorized by color but by tempeture. Which I mean I guess it sorta means their catagorized by color but thats being nitpicky. Our sun is 5,772 K, which according to wikipedia means its a class-G star which is known by the not nerds as a yellow dwarf. Being a physicist means Randell is VERY aware of the category of our Sun. Repeat, the Sun is called a "yellow dwarf", therefore is Ponytail said "white star", she'd be talking about a star that is 9000 K and therfor NOT our Sun. Seriously this was like a 5 minute google search. [[User:Apollo11|Apollo11]] ([[User talk:Apollo11|talk]]) 21:01, 13 January 2025 (UTC)
::: At any rate, I believe it plays into Ponytail just goofing around more than being precise [[User:Starstar|Starstar]] ([[User talk:Starstar|talk]]) 22:12, 13 January 2025 (UTC)
:Perhaps it is intentional? [[User:Starstar|Starstar]] ([[User talk:Starstar|talk]]) 20:36, 13 January 2025 (UTC)

Possible trivia: The effect used in the title text for "²³⁸Umbrella" does NOT use html formatting. It uses unicode for the almost-but-not-technically superscripted "238" before "Umbrella." On some systems, this renders with the "23" being larger than and slightly below the level of the "8". Whether Randall knew of this effect or not is a mystery. If he did know, his motivations are a mystery. Maybe the 8 is radioactive and emitted a non-massless particle, thereby making it smaller (less mass != less volume, but go with it here) and more buoyant (less weight) in the presence of the adjacent characters. [[Special:Contributions/198.41.227.105|198.41.227.105]] 21:19, 13 January 2025 (UTC)
:You can't use HTML markup in the title attribute, so there's no other way to do super/sub-scripting there. He could have used JavaScript to emulate the title attribute, though. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:38, 13 January 2025 (UTC)
::I see no issue with the title text's 238 when on a PC neither on xkcd or here. The numbers are all similar. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:22, 14 January 2025 (UTC)

What do people think of Hairstylist Wannabe's near-total rewrite of the explanation? While they added lots of technical details about radon, I think they missed much of the humor. Ponytail's comments are typical of the kind of things a home inspector or repair person will say to the owner, not really "flippant". [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:48, 13 January 2025 (UTC)
:I like the facts but i changed the joke explantion back. [[User:Apollo11|Apollo11]] ([[User talk:Apollo11|talk]]) 22:07, 13 January 2025 (UTC)
:The rewrite has waaaaay too much detail. This site is for explaining what's going on in a comic, not repeating everything you know that's related, however remotely, to the comic. Just add wikilinks to things! Like, do we really need to have repeated here how much <sup>238</sup>U the Earth contains? How much radiation one experiences from uranium? I vote to remove a lot of the detail and just explain the comic. [[User:DKMell|DKMell]] ([[User talk:DKMell|talk]]) 23:45, 13 January 2025 (UTC)

Possible trivia: 238 Umbrella is a common weight for a patio umbrella stand. {{unsigned|TallJason|22:53, 13 January 2025}}

I started to write another paragraph:
:The primary reason why the radon is considered more deadly than the original uranium (and thorium) is its nature as a heavy gas; the earlier states of decay remain stuck in the original rock, interstitially, whereas radon more freely leaches out. This quickly disperses to extremely diluted levels in the open air but, being a gas that is denser than air, it can accumulate to low (but potentially significant) levels in a cellar or basement, having few natural air-currents to drive the heavier gas atoms out of the sump in which the radon sits. Although each atom does not last long in this state, the resulting polonium, bismuth or lead atoms (all being isotopes that are themselves radioactive) ''can'' find themselves drifting as dust particles initially (and, after settling, easily disturbed), with the potential
...but it got out of hand. Was going to edit it down (and correct anything I'd accidentally mispoken/misedited/ispunctuated, in the initial fervour) when I'd finished, but I've got to go somewhere, so leaving it as possible inspiration for someone else to use/ignore/tear part/whatever. Have fun. [[Special:Contributions/172.68.205.92|172.68.205.92]] 23:50, 13 January 2025 (UTC)
: "possible inspiration for someone else" Good stuff, but surely it already exists (without xkcd context) many other places? Can be just linked? [[User:PRR|PRR]] ([[User talk:PRR|talk]]) 02:33, 14 January 2025 (UTC)

I thought, the title text was a reference to nuclear umbrella. [[Special:Contributions/172.68.50.200|172.68.50.200]] 07:45, 14 January 2025 (UTC)

"This process will render the Earth uninhabitable for humans within approximately 5 billion years." That seems very optimistic. Isn't it more like 1 billion years? --[[User:Coconut Galaxy|Coconut Galaxy]] ([[User talk:Coconut Galaxy|talk]]) 10:05, 14 January 2025 (UTC)
:Yes the Earth will become uninhabitable in close to but less than a billion years. But not because the sun is expanding at the end of it's life. But because it gets hotter and begins to strip the Earths atmosphere, and this also means the end of the oceans. When they are gone, complicated life forms should not be possible. Bacteria could live until the sun possibly engulfs the Earth (it is not certain if this will happen though.) --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 12:22, 14 January 2025 (UTC)

== Radon and Radium spectral lines ==

This comic sparked a tangentially related discussion at [https://en.wikipedia.org/wiki/Wikipedia_talk:WikiProject_Chemistry#Radon_and_Radium_spectral_lines Wikipedia talk:WikiProject Chemistry#Radon and Radium spectral lines], leading to the discovery that the spectra given on Wikipedia for multiple chemical elements (including Radon) had been wrong since 2013 -- the result of a bug in a 15-year-old Matlab plugin. [[User:Rexon Mobile|Rexon Mobile]] ([[User talk:Rexon Mobile|talk]]) 17:03, 14 January 2025 (UTC)

== Radiation dose ==

I'm removing this paragraph entirely, since it's wildly incorrect and adding negative value; I may or may not have time to add a more accurate discussion later, if someone else hasn't done so first:

<blockquote>The actual amount of uranium experienced</blockquote>

You're actually talking about the total background radiation exposure, not specifically radiation from uranium (and one wouldn't normally describe exposure to radiation from uranium as "experiencing uranium" in any event).

<blockquote>in any given environment,</blockquote>

No, on average across all individuals, in all environments; the amount of background radiation exposure will be much higher in some environments than in others.

<blockquote>according to Randall's own Radiation chart, is 10 microsieverts worth of radiation, on average,</blockquote>

Across all individuals.

<blockquote>over a year</blockquote>

Over a ''day''. It literally says that in the entry in the chart.

<blockquote>the amount in one's body,</blockquote>

The amount of radiation exposure due to potassium decay within one's body.

<blockquote>in contrast, is about 390 microsievert over that same timeframe,</blockquote>

No, that one actually is per year.

<blockquote>again on average. The lowest dose linked to any serious risk is in the millisievert range, over thousands of times stronger than any of these sources. Thus the radiation from radon buildup in a normal house is not of concern,</blockquote>

No, the ''average'' amount of radiation exposure per individual -- averaged across the entire population, who vary wildly in not only the uranium content of the local soil, but also the characteristics of their basements, and even in whether they ''have'' a basement at all -- is not a concern. There are plenty of "normal" houses in which the radiation from radon buildup is a concern; there are just also plenty of other "normal" houses in which it is not.

<blockquote>as long as it is properly managed in time. Instead it is radon's toxicity that is the problem, both from the radon itself and its "daughter" isotopes, that poses a danger to humans.</blockquote>

This is absolutely false. Radon and its daughter products are dangerous to humans precisely because of the ionizing radiation they emit, which has a tendency to produce lung cancer when decay occurs within the lungs (in the inhaled air for radon itself, or attached to floating dust particles for daughter isotopes). Radon itself isn't poisonous in a chemical sense at all -- as a noble gas, it doesn't react with other substances under normal conditions. Some of the daughter products ''are'' chemically poisonous, but are still far more dangerous for their radioactivity than for their chemical properties (e.g., lead-214 is far more dangerous than a similar quantity of any of the stable lead isotopes (206, 207, and 208)).[[Special:Contributions/172.70.127.191|172.70.127.191]] 20:35, 14 January 2025 (UTC)

I think the title text has umbrella and cover because umbrellas cover things. {{unsigned|Awesome person|20:47, 15 January 2025}}

3032: Skew-T Log-P

2025-01-02T16:47:54Z

141.101.98.172: /* Explanation */ Better (more correct?) way of putting this.

{{comic
| number = 3032
| date = January 1, 2025
| title = Skew-T Log-P
| image = skew_t_log_p_2x.png
| imagesize = 569x626px
| noexpand = true
| titletext = The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second.
}}

==Explanation==
{{incomplete|Created by a BOT CLEANING UP AFTER DAVE - This needs an explanation. Table not filled out. Also the title text was not mentioned at all. I added a very simple start to this, but nothing about what the product actually means, please expand... Do NOT delete this tag too soon.}}
A {{w|skew-T log-P diagram}} (the name comes from the temperature (T) lines being skewed at a 45-degree angle, and the pressure (P) lines being logarithmic in scale) are mostly used to plot {{w|atmospheric sounding}}s, which are usually made by sending a weather balloon up into the air.

Because the diagrams have a lot of lines on them (isobars, isotherms, adiabats, and mixing ratios, and that's before plotting the actual measurements of temperature and dewpoint temperature), they can be hard to understand if you haven't learned how to. The comic pretends to offer an explanation of how to interpret one such diagram (which may appear to have measurements from two separate weather balloons, one with two solid black lines for its measurements and the other with two dashed black lines, whereas the two lines and various styles of line generally mean different measurements from the same balloon-track or other means of obtaining atmospheric readings), but most of the explanations are blatantly incorrect or humorous in nature. See details in the [[#Table with terms|table]] below.

In the title text it is stated that "The most important quantity for meteorologists is of course the product of latent pressure and temperostrophic enthalpy, though 'how nice the weather is' is a close second". So it jokes by comparing a complicated produkt with a simple sentence about how nice the weather is.

[[File:Annotated_Skew_T_diagram.png|thumb|An actual Skew-T Log-P diagram, with several real annotations.]]The true design of a Skew-T Log-P diagram is intended to best represent the nature of the weather in any given column of atmosphere. The pressure (vertical axis, with pressure being closely but not directly inversely synonymous to altitude) is shown as a logarithmic scale (i.e. Log-P) due to the more practical separation of values. Plotting pressure proportionately (which must also be from top to bottom, to match its general relationship with altitude) would space features out in ways that would be hard to use and interpret, whereas the logarithmic scale is far more pragmatic. The temperature scale is deliberately tilted, rather than orthagonal, which (together with the logarithmic nature of the inverted pressure scale) allows the typical way that temperatures fall with altitude(≈as pressure falls) to trend roughly vertically, give or take the notable changes that are key to understanding the forecast. Other measurement lines, differently skewed and often also curving across the temperature/pressure skewed-log 'grid', represent various other idealistic relationships (where both T and P vary, keeping another measure constant) that are useful references to meteorologists.

Upon this style of graph are plotted the ''actual'' measurements obtained by (e.g.) releasing a weather balloon. As well as the variation of actual temperatures and pressures, other retrieved data is plotted, such the {{w|dew point}}. The dew point is a function of how the humidity of the air interacts with any given temperature and pressure to produce condensation. By observing how the actual measurements and dew point line converge and cross, the development and nature of clouds can be tracked and pinned to specific cloud layers. Further details may also be included, such as wind-direction and wind-speed indications (often to the side of the plot) to give a visual cue about possible {{w|wind shear}} and/or to suggest which direction of adjacent weather-station readings may hold clues as to what changes may later blow in above the current site.

==Table with terms==
{| class="wikitable" | style="background:#E6C3C3;"
!Item in comic
!Correct?
!Explanation
|-
| Pressure latitude || ||
|-
| Enthalpic pressure || ||
|-
| Entropic density || ||
|-
| Latent heat of cooling || ||
|-
| Isobars || Yes || Lines denoting equal ("{{wiktionary|iso-}}") air pressure ("{{wiktionary|bar-|-bar}}"), probably most often recognised as the indicators of how ground-level pressures change (or not) across the horizontal area depicted on a weather ''map''. Tightly packed isobars would indicate stronger winds, which (away from the tropics) would generally be either clockwise or anti-clockwise around the centre of the dominant isobar feature, depending upon whether that's a high pressure or a low pressure and (away from the tropics) which hemisphere.
In this type of chart, which depicts data obtained from above a single point, it has the same meaning but is instead a pre-existing reference line across which the actual data is plotted, and does not itself indicate the nature of any wind.
|-
| Omnitrophic wind || ||
|-
| Isomers || No || Different forms of molecules with the same formula, with the atoms or functional groups arranged differently. An example would be propanol, which has three. One of the most common isomers of propanol has its OH functional group in the middle, so is called isopropyl alcohol or isopropanol.
However, these are actually iso'''therm''' lines, representing equal temperature.
|-
| These lines are slightly different because Dave messed them up || No || Indicating isotherms (or, according to the comic, "isomers"), the suggestion is that slightly wrong lines were drawn by Dave and had to be corrected.
The real reason for the not quite identical lines is that the measured temperature at a given pressure can be converted to or from the ''potential'' temperature that the same air would have if at a standard pressure (holding the same amount of heat energy). For practical reasons, both for composing and interpreting the eventual plot, each of the slightly differently skewed isotherms are given, usually in clearly differentiable styles of line.
|-
| Line of constant thermodynamics || ||
|-
| Uncomfortably moist adiabat || Wrongly placed, unusually qualified|| This labels a segment of isotherm, which is the exact 'opposite' of an idiabat.
An adiabat is a line along which temperature can change for a given mass, without changing the amount of energy. This is primarily made possible by changing the density (by a change in pressure) of the gas. There are typically two types of adiabat, marked for reference on the plot, "dry adiabat" (curves across the isotherms perpendicularly, to create a largely square but slightly curved grid with them), and "moist/saturated adiabat" (the latter's heat-maintaining profile is influenced greatly by the humidity content, and produces graphing lines vastly different from the equivalent "dry" versions). Randall has declared this (erroneous) type of adiabat to be "uncomfortably" moist, so presumably not totally saturated but also not subjectively 'pleasant'.
|-
| Oops, the balloon flew through a ghost || ||
|-
| No birds up here :( || Yes* || This point is near the top of the diagram, with an air pressure of about 110 millibar (about 15 kilometers above sea level). This is well above the highest flight height of any known bird species. However, this information is irrelevant to the purpose of a skew-T log-P diagram.
|-
| Track of rising weather balloon || ||
|-
| Track of popped balloon falling back down || ||
|-
| Meteogenesis || ||
|-
| Seems bad || ||
|-
| Dew point || Wrongly represented. || The temperature at which water condenses out of the air, and therefore dew starts to form, given the level of water vapor in the air.
It is shown here as an ''actual'' singular point, when it should be a line (typically the leftmost solid plotted line) representive of which temperature 'dew' should form at any given pressure.
|-
| Humidor || No || In reality, is a {{w|Humidor|container}} that is used maintain a more controllable humidity within which to store smoking products.
In the graph, points at the line that is probably representing the dew point, which is represents the nature of the ''actual'' humidity encountered.
|-
| Heavyside layer || No || Probably a misspelling of "Heaviside," the surname of the co-discoverer of what we now call the E region of the ionosphere. Co-discovered by Arthur E. Kennelly and Oliver Heaviside.
In this diagram it is apparently labeling a heavily marked isotherm, or line of constant temperature. Most likely it indicates the 0°C line, this being importantly indicative of the freezing point of water.
|-
| These lines are tilted because the wind is blowing them || No || The wind is not actually a derivable featured of this diagram, which does not have data of either direction or strength of air movement.
These lines are actually dry adiabats (see above), possibly two sets due to a similar renormalised interpretation, as with the isotherms, at a given reference pressure.
|-
| Don't stand here or you might get hit by a balloon || ||
|}

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

:How to interpret a skew-T log-P diagram
:[The comic shows a skew-T log-P diagram. On it are various labels, including isobars, comments, and other interpretations of the diagram.]
:[Left to the diagram is an upwards-pointing arrow with the label "Pressure Latitude". Right to the diagram is a downwards-pointing arrow with the label "Entropic Density". Below the diagram is a right-pointing arrow with the label "Enthalpic Pressure".]
:[The remaining various labels are inside the diagram.]

==Trivia==
*Even though this comic was released on New Year's Day 2025, it was not a [[:Category:New Year|New Year comic]].
**Only second time this has happened since New Year comics became a regular thing from 2011.

{{comic discussion}}

[[Category:Charts]]
[[Category:Weather]]

2789: Making Plans

2023-06-15T12:28:32Z

141.101.98.172: /* Explanation */ seeing 4 full stops together hurt me almost physically. Ellipses are ALWAYS 3. Never 2, never 4, never even more than 4. Anyway, I don't think ellipses even make sense here.

{{comic
| number = 2789
| date = June 14, 2023
| title = Making Plans
| image = making_plans_2x.png
| imagesize = 217x396px
| noexpand = true
| titletext = Oh no, I haven't checked in with Yvonne in YEARS.
}}

==Explanation==
{{incomplete|Created by ABBIE, ABRAHAM, and an AARDVARK alias AARON. Do NOT delete this tag too soon.}}

This comic is about biases created from {{w|alphabetical order}}. According to Wikipedia, "The practice in certain fields of ordering citations in bibliographies by the surnames of their authors has been found to create bias in favor of authors with surnames which appear earlier in the alphabet, while this effect does not appear in fields in which bibliographies are ordered chronologically."[https://decisionslab.unl.edu/pubs/stevens_duque_2018_SM.pdf]. Similar effects have also been identified with the ordering of candidates on ballot papers[https://electionlab.mit.edu/research/ballot-order-effects]. In essence, humans tend to favor whatever is at the top of any given list or data set, or may only assess the first few options until they reach one that is 'good enough', thus never evaluating those further down the list; this is one reason why randomness is important in any scientifically rigorous trial.

In the comic, [[Cueball]] is telling [[Megan]] about some of his upcoming plans; tonight he had arranged a meet-up with contacts whose names start with A or B, tomorrow's socializing involves a larger group of A-contacts, but there seems some doubt over some of them. It is possible his well-intentioned invites went to defunct/long-unchecked destinations, or the recipients were disinclined to respond to an 'old flame' who suddenly re-establishes contact out of the blue. Alternately, they cannot take seriously an invite to an event far from their current location, or else Cueball has Cc:ed them all and entirely forgotten some personal enmities between some of those he grouped together.

By this point, there is a clear pattern: Cueball has started contacting friends based upon their alphabetical priority in his list of names, instead of making more practical social decisions, such as maintaining contact with those who (regardless of name) are already in more recent contact. Although, arguably, this would also be socially detrimental; anyone who happened to descend out of "recent contact" might never be contacted ''ever again''. These social pitfalls are something that almost everyone has to try to deal with, but Cueball's 'logical' way of handling it is ironically one of the more socially illogical methods available.

The title text continues the joke, implying that Cueball rarely makes it to the bottom of his alphabetical list; as such, he has not reached out to his friend Yvonne in a very long time. She may even have assumed he has been {{w|Ghosting (behavior)|ghosting}} her, having seemingly not attempted to make return contact for that while either, but Cueball seems unable to distinguish between willing and enthusiastic contacts in general so his general social ineptness may be as much to blame as the enforced alphabetical priority of his friendship groups.

==Transcript==
:[Cueball is talking to Megan.]
:Cueball: Tonight is pub trivia with Annie and Beth.
:Cueball: And tomorrow Alex and I are seeing a movie. I also invited Andrew and Amy but I haven't heard back.

:[Caption below the panel:]
:I'm realizing I should really switch to sorting my phone contacts by most recent.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Phones]]
[[Category:Social interactions]]

2783: Ruling Out

2023-06-08T17:42:34Z

141.101.98.172:

{{comic
| number = 2783
| date = May 31, 2023
| title = Ruling Out
| image = ruling_out_2x.png
| imagesize = 295x396px
| noexpand = true
| titletext = We were able to replicate and confirm prior authors' detection of a moon orbiting the Earth with high confidence.
}}

==Explanation==
{{incomplete|Created by a TECTONICALLY-ACTIVE BOT WITH SUBSURFACE OCEANS. Do NOT rule out this tag too soon.}}

Most science studies are intended to discover new knowledge. In astronomy, the goal is often to find different types of objects in space, or learn how astronomical objects are formed and behave. But often from studying things that exist, we also learn about limits of the kinds of things that ''can'' exist; when this happens, we say that we've "ruled out" the excluded phenomena.

[[Cueball]] lists five obviously impossible objects.{{Citation needed}}

* "Earthlike stars": A play on "Earth-like planets" which scientists are very interested in finding. The [https://solarsystem.nasa.gov/planets/earth/overview/ Earth] is not a {{w|star}}{{Citation needed}}, hence stars cannot be Earthlike.
: Searches for both {{w|List of potentially habitable exoplanets|Earth-like planets}} and {{w|Solar analog|Sun-like stars}} go unabated, with various near matches found.

* "Exoplanets in our solar system": {{w|Exoplanet}}s are by definition not in our solar system.
: Planets in our solar system (even {{w|Planets beyond Neptune|undiscovered ones}}) are unaffected, as is the {{w|List of exoplanet search projects|search for exoplanets}} around other stars, with conclusive evidence of both.

* "Habitable-zone quasars": {{w|Quasar}}s in the {{w|habitable zone}}s of stars are only theoretically feasible for relatively small {{w|black hole}}s with active {{w|accretion disk}}s in a star's habitable zone, visible from the Earth and brighter than the Sun, because of the technical criteria for classifying them in terms of their {{w|apparent magnitude}} relative to that of their galaxy.[https://iopscience.iop.org/article/10.1088/0004-637X/728/1/26] None such have ever been observed.{{fact}} While typical galaxies usually have only one quasar in their center, merging galaxies often have two far apart. Perhaps in 4-5 billion years, when the {{w|Andromeda Galaxy}} merges with our {{w|Milky Way}}, its [https://www.sci.news/astronomy/article00779.html microquasar] might qualify, but that is extremely unlikely.
:While not certain, habitable zones around some quasars have not been ruled out.[https://iopscience.iop.org/article/10.3847/1538-4357/ab1b2f/meta][https://iopscience.iop.org/article/10.1088/1742-6596/2364/1/012057/meta]

* "Stars with subsurface oceans": Because the temperatures inside stars are higher than that which can support the existence of liquids as we understand them, stars cannot have subsurface oceans. After many billions of years, a {{w|white dwarf}} will cool to the point where it no longer emits significant heat or light, becoming a {{w|black dwarf}}, eventually cooling to the point where it might develop subsurface liquids.{{acn}} However, the universe is not old enough for any black dwarfs to exist yet,[https://iopscience.iop.org/article/10.1086/375341/pdf] and sufficiently cool black dwarfs might not even be considered stars, but rather {{w|rogue planet}}s.
: The possibility of subsurface oceans within various planets and moons is an {{w|Extraterrestrial liquid water|active subject of study}}, and was previously mentioned 10 comics ago in [[2773: Planetary Scientist]].

* "Tectonically active black holes": Black holes do not have {{w|tectonic plate}}s, so they cannot be tectonically active.
: There are theories that neutron stars can exhibit {{w|Quake (natural phenomenon)#Starquake|tectonic-like movements}} (as some of the more typical rocky bodies certainly do), but the physics of the 'inside' of a black hole are thought to involve {{w|Black hole#Singularity|strange physics}} incompatible with any form of geology, and cannot be observed anyway – it is believed that the only externally-observable properties of black holes are mass, electric charge, and angular momentum, poetically called the '{{w|no-hair theorem}}'.

The joke is that you don't actually have to study anything to come to these almost patently obvious conclusions. The counter-proposals would need far more effort to even justify them as valid theories, by common understanding, and greater still to try to observe any supporting proof.

Some studies are also done to confirm the results of previous studies, to ensure that the conclusions were not mistaken or a fluke. The title text describes a study that was done to confirm the existence of a moon orbiting Earth, even though any sighted person can walk outside and see the Moon, the existence of the Moon has been known for at least as long as humanity has existed, and the fact that it orbits the Earth has been assumed or known for upwards of 3,000 years. The ancient Greeks and Babylonians, for example, thought that the Moon orbited the Earth, though they lacked a detailed physical understanding of the system (they also believed, erroneously, that {{w|Geocentric model|everything else in the universe orbited the Earth too}}). {{w|Anaxagoras}} (c. 500–428 BC) is credited with the correct explanation of lunar eclipses, and reportedly was the first to explain that the Moon shines due to reflected light from the Sun. However, it was not until the work of {{w|Nicolaus Copernicus}} in the 16th century that a detailed and accurate model of the Moon's orbit around the Earth was developed. Regardless, at this stage, a study to confirm the validity of Copernican orbits would contribute nothing to the scientific process, much less a study confirming the mere existence of the Moon.

==Transcript==

:[Cueball is talking to Megan.]
:Cueball: So far our astronomy group has published studies ruling out the existence of Earthlike stars, exoplanets in our solar system, habitable-zone quasars, stars with subsurface oceans, and tectonically active black holes.

:[Caption below the panel:]
:Science got way easier when we realized you were allowed to do studies just to rule stuff out.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Astronomy]]
[[Category:Science]]

2007: Brookhaven RHIC

2018-06-15T16:34:04Z

141.101.98.172:

{{comic
| number = 2007
| date = June 15, 2018
| title = Brookhaven RHIC
| image = brookhaven_rhic.png
| titletext = "Buddy, you trying to pull something? I can't buy this gold--all the electrons are missing. I could face serious charges!"
}}

==Explanation==
{{incomplete|Created by a CASH FOR GOLD SALESMAN - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
The {{w|Relativistic Heavy Ion Collider}} is a particle accelerator designed to collide gold ions together at incredibly high speeds. This is normally done to study particle physics - the high-energy collisions allow us to learn more about how subatomic particles behave.

Randall proposes that, instead of using the beam of gold ions for particle collisions, it should be diverted and sold at cash-for-gold stores to make money. The joke is that because they are traveling at relativistic speeds, the mass of the particles being sold will be much more than the mass of the ions being supplied to the collider's input. However, it would be very difficult to sell a beam of charged particles. The amount of gold involved is microscopic, and since the particle beam is moving at relativistic speeds, it wouldn't stay in the shop long enough to make a sale{{Citation needed}}. It would also be very dangerous. This is probably why Brookhaven rejected Randall's proposal. Randall has done many comics describing impractical research proposals.

The title text imagines the owner of the stores complaining about the sale, not because of impracticality, but because Randall is selling gold ions (including the entire positively-charged nucleus of the gold atom and 32 of 79 electrons stripped from the gold atom https://en.wikipedia.org/wiki/Relativistic_Heavy_Ion_Collider) instead of normal, electrically neutral gold atoms. This is a pun on the word "charges", which could refer to {{w|electric charge}} or to {{w|criminal charge|criminal charges}}.

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

{{comic discussion}}

Talk:1907: Immune System

2017-10-27T16:24:37Z

141.101.98.172:

Actually, there are many "biologics" -- drugs that suppress the various facets of the immune system to treat diseases like Rheumatoid Arthritis (R.A.). Examples include Enbrel and Remicade. --[[User:Pondy|Pondy]] ([[User talk:Pondy|talk]]) 16:55, 25 October 2017 (UTC)

We have to add a [citation needed] here. [[Special:Contributions/172.68.47.114|172.68.47.114]] 18:06, 25 October 2017 (UTC)
:{{Citation needed}} [[Special:Contributions/162.158.62.93|162.158.62.93]] 19:57, 26 October 2017 (UTC)

Is Randall really suggesting using his own immune system as the [[wikipedia:Good_cop/bad_cop|Bad Cop]]?

Add a line or two about gullible managers who will believe anything as long as it is presented in a shiny PowerPoint presentation.--[[Special:Contributions/162.158.150.46|162.158.150.46]] 21:35, 25 October 2017 (UTC)

I'd question the assertion that "Ponytail is delivering an informative report" - more likely it's an ''un''informative report, which is why she felt the need to spice it up with a sensationalist (and irrelevant) account of her immune system.[[Special:Contributions/141.101.98.172|141.101.98.172]] 16:24, 27 October 2017 (UTC)

1907: Immune System

2017-10-27T16:20:43Z

141.101.98.172: /* Explanation */

{{comic
| number = 1907
| date = October 25, 2017
| title = Immune System
| image = immune_system.png
| titletext = It also helps with negotiation. "Look, if it were up to me, *I'd* accept your offer, but my swarm of autonomous killer cells literally can't be reasoned with. It's out of my hands!"
}}

==Explanation==
In this comic, Ponytail is delivering an informative report to a group of listeners, likely important managers of some large company. She begins her lecture by stating she is the host of a microscopic autonomous swarm that will do anything to protect her. She is referring to the immune system, which could technically be defined as a "microscopic autonomous swarm" that will do anything to protect her -- i.e destroy pathogens such as viruses and bacteria, both of which cause multitudinous diseases in humans. Like many of the systems of the body, the immune system cannot be controlled by conscious thought, and should not be taken as unordinary.

The caption below reveals the method behind her madness. Randall claims that beginning any business presentation with a surreal description of one's own immune system is guaranteed to strengthen your case. Whether or not this is actually the case is irrelevant, the point of the comic is about "how cool the immune system is", and explains its coolness through an unconventional description of how the process works. Additionally, Ponytail's description implies more potential power than an immune system typically has, perhaps to to gain more respect/fear from the speaker's audience.

The title text elaborates further on this, stating that similar arguments can be used in negotiation. The description of the immune system is deliberately misleading, implying that the immune system may attack the other negotiator if the terms of the deal aren't satisfactory. While it is correct that your immune cells cannot be reasoned with{{Citation needed}} and theoretically it could cause an anaphylactic shock in the targeted organism, the veiled threat omits the fact that the immune system 1) is unaffected by external negotiations conducted by its host, 2) is incapable of attacking things outside of the body, and 3) would have to overcome the target's own immune system.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Ponytail is standing in front of a boardroom, holding a stick up to the board. Cueball, Megan and Hairbun are in the audience, sitting at a long table; an extra, unoccupied chair is in the front.]
:Ponytail: My body hosts an autonomous microscopic defensive swarm that will do anything to protect me.
:Ponytail: I have no ability to restrain it and I don't know my own power.
:Ponytail: So listen up.
:Ponytail: Sales grew by 4% this quarter...

:[Caption below the panel:]
:Business protip: You can strengthen any presentation by opening with a reminder about how cool immune systems are.

{{comic discussion}}

[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hairbun]]

Talk:1901: Logical

2017-10-13T11:55:13Z

141.101.98.172:

Potentially relevant: [http://www.tandfonline.com/doi/pdf/10.1080/00224545.1954.9919125]
Potentially relevant: [https://www.youtube.com/watch?v=VdtwTeBPYQA]
Potentially relevant: [http://www.jstor.org/stable/1821269?seq=1#page_scan_tab_contents]
[[User:Joshupetersen|Joshupetersen]] ([[User talk:Joshupetersen|talk]]) 16:00, 11 October 2017 (UTC)

-- Link 1 points to a 1952 paper which demonstrates that "scientists" live longer with the top 6 occupations being Educators, Lawyers, Engineers, Naturalists, Historians and Inventors ... seems a pretty loose definition of scientist to me. --[[User:Rtanenbaum|Rtanenbaum]] ([[User talk:Rtanenbaum|talk]]) 17:39, 11 October 2017 (UTC)

Added the title text to the explanation and transcript. --[[User:JayRulesXKCD|'''JayRules''XKCD''' ]]<sup>[[User talk:JayRulesXKCD|what's up?]]</sup> 16:06, 11 October 2017 (UTC)

For the record I believe the advantages of using statistics over intuition were thoroughly discussed in the Michael Lewis book [https://en.wikipedia.org/wiki/Moneyball ''Moneyball''], also 538 has done studies comparing statistical approaches to election prediction to political punditry and finally the good old [https://en.wikipedia.org/wiki/Monty_Hall_Problem Monty Hall Problem].[[User:Sturmovik|Sturmovik]] ([[User talk:Sturmovik|talk]]) 16:22, 11 October 2017 (UTC)

"... inconclusive scientific evidence against White Hat's position"? Is "inconclusive" the best you can do? Or did you mean "''only'' inconclusive"? Randall is basically attempting to use an argument from silence against anyone asserting White Hat's basic position (for which there is some very good evidence). It's ironic that to argue against the position requires using the law of non-contradiction; hence is self refuting. [[Special:Contributions/198.41.238.52|198.41.238.52]] 22:41, 11 October 2017 (UTC)

This comic is probably a response to the Nobel prize in economics awarded to Richard Thaler for finding ways to nudge people to decisions that the nudger believes to be more common sense.--[[Special:Contributions/162.158.88.188|162.158.88.188]] 09:23, 12 October 2017 (UTC)

The problem with generalizations is that all of them are idiotic.--[[Special:Contributions/162.158.111.151|162.158.111.151]] 12:14, 12 October 2017 (UTC)
: ... including the one you just used :-). -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:49, 13 October 2017 (UTC)
:: *Whoosh!*[[Special:Contributions/141.101.98.172|141.101.98.172]] 11:55, 13 October 2017 (UTC)

1897: Self Driving

2017-10-03T08:19:52Z

141.101.98.172: /* Explanation */

{{comic
| number = 1897
| date = October 2, 2017
| title = Self Driving
| image = self_driving.png
| titletext = "Crowdsourced steering" doesn't sound quite as appealing as "self driving."
}}

==Explanation==
{{incomplete|First draft}}
This comic references the approach of using {{w|CAPTCHA}}<nowiki>s</nowiki> input to solve problems, particularly those involving image classification, which are not solvable by computers.

Such an approach can serve to create the learning set as the basis for training an artificial intelligence to better recognise or respond to similar stimuli. This approach was used by Google to identify house numbers for Google Street View, and nowadays Google also uses CAPTCHAs to identify street signs and objects in pictures. This might be a reasonable way to help improve the performance of the AI in a self-driving car that responds to video input, by reviewing images it might encounter and flagging road signs, etc. that it should respond to.

However, the temptation might be to simply sidestep the hard problem of AI by having all instances 'solved' by "offloading [the] work onto random strangers" through CAPTCHAs. For example, this has been used to defeat CAPTCHAs themselves; people were asked to solve captchas to unlock pornographic images in a computer game, while the solution for the captcha was relayed to a server belonging to cybercriminals.<ref>http://news.bbc.co.uk/2/hi/technology/7067962.stm and https://doi.org/10.1016/S1353-4858(08)70036-9</ref>

Alarmingly, the developers of this 'self-driving' car seem to have gone for the lazy approach. Instead of teaching an AI, the CAPTCHA answer is used in real time to check whether the "self-driving" car is about to arrive at an intersection with a stop sign. This information is pretty critical, as failing to mark the stop could cause an accident. The user is unlikely to respond to the CAPTCHA in time to avert disaster, not to mention that any interruption to the car's internet connection could prove fatal.

The title text explains that this method could be called "crowdsourced steering", {{w|crowdsourcing}} meaning sending the data on the internet to let several users provide their ideas and input on a problem, but that this doesn't sound as safe as "self driving".

This also suggests that Randall is a bit skeptical of the current stage of AI, as this doubts whether the AI technology really is working in the way that we expect. It also comments on how what we call 'progress' actually is putting our work onto other people.

==Transcript==
:[Inside a frame there is the following text above an image:]
:To complete your registration, please tell us whether or not this image contains a stop sign:

:[The square image is a drawing of a road leading up to a sign post with a hard to read word at the top part of the sign. The sign also has two smaller signs left and right with unreadable text. The image is of poor quality, but trees and other obstacles next to the road can be seen. Darkness around the edges of the image could indicate that it is night and the landscape is only lit up by a cars head lights.]
:Sign: Stop

:[Beneath the image there are two large gray buttons with a word in each:]
:No Yes

:[Beneath the buttons are the following text:]
:Answer quickly-our self-driving car is almost at the intersection.

:[Caption beneath the frame:]
:So much of "AI" is just figuring out way to offload work onto random strangers.

{{comic discussion}}

<references/>

1820: Security Advice

2017-04-05T14:52:36Z

141.101.98.172: /* Security Tip Explanations */ Added explanation regarding prime numbers

{{comic
| number = 1820
| date = April 5, 2017
| title = Security Advice
| image = security_advice.png
| titletext = Never give your password or bank account number to anyone who doesn't have a blue check mark next to their name.
}}

==Explanation==
{{incomplete|Incomplete. TBD:Complete tip explanations Do NOT delete this tag too soon.}}

The comic depicts a conversation between [[Cueball]] and [[Ponytail]], discussing the fact that giving people security advice has failed to improve their internet security, and in some cases even made things worse (such as requiring complicated passwords leading to people leaving post-it notes with their passwords on their screen, leading to huge security risks). As a result Cueball suggests {{w|reverse psychology|giving bad advice instead}}, in hopes of a positive effect. The last panel contains a list these security tips, which are parodies of actual security tips.

The last tip on the image is most likely a reference to Ingmar Bergman's film [https://en.wikipedia.org/wiki/The_Seventh_Seal#Synopsis The Seventh Seal].

===Security Tip Explanations===
{| class="wikitable"
!Security Tip
!Explanation
|-
|Don't click links to websites
|The usual tip is "Don't click on ''suspicious'' website links." The comic's variation instead implies don't click on any links to any websites, or don't use the internet.
|-
|Use prime numbers in your password
|Long prime numbers are an essential part of modern cryptography and security systems, but difficult to remember and therefore very inconvenient as a password.
|-
|Change your password manager monthly
|
|-
|Hold your breath while crossing the border
|This in its self, wouldn't do anything, but if you hold your breath for too long you could pass out when crossing, or look stressed/suspicious. Overall, this would not help you.
|-
|Install a secure font
|
|-
|Use a 2-factor smoke detector
|A new way to keep accounts secure is 2-factor authentication, which usually means you enter your password, and then look for an email (or go into a mobile app) with a code which you then enter into the website. A 2-factor smoke detector would be useless, because it would require you to verify that there is actually a fire with a code, when the purpose of smoke detectors are to warn you about fires you ''don't'' know about.
|-
|Change your maiden name regularly
|A common security question (a type of 2-factor authentication from the previous tip) asks you for your maiden name.
|-
|Put strange USB drives in a bag of rice overnight
|The usual security tip is "Don't plug strange USB drives into your computer," because sometimes attackers put viruses that infect your system when plugged in. This tip implies that you should "put USB drives in a bag of rice overnight" which is a common technique for drying out water damaged devices, due to rice's absorbent qualities. This would not clean the drive of viruses, and unless the drive was wet (perhaps because you found it outside due to it being called "strange") it would not do anything.
|-
|Use special characters like & and %
|
|-
|Only read content published through Tor.com
|[https://en.wikipedia.org/wiki/Tor_(anonymity_network) Tor] is a software solution to provide anonymity on the web for its users. The website [https://tor.com Tor.com] is the website of fantasy and sci-fi book publisher Tor, which has no relation to the Tor-network.
|-
|Use a burner's phone
|
|-
|Get an SSL certificate and store it in a safe place
|
|-
|If a border guard asks to examine your laptop, you have a legal right to challenge them to a chess game for your soul.
|This tip is likely a reference to Ingmar Bergman's film [https://en.wikipedia.org/wiki/The_Seventh_Seal#Synopsis The Seventh Seal]
|-
|Never give your password or bank account number to anyone who doesn't have a blue check mark next to their name. (Title Text)
|The usual security tip here is ''"only trust accounts claiming to he legitimate if they have a blue check mark next to their name"'', which means that the account is verified as legitimate. This tip suggests only giving your ''password'' to verified accounts, although you shouldn't give your password to ''any'' account.
|}

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

:Ponytail: We've been trying for decades to give people good security advice.
:Ponytail: But in retrospect, lots of the tips actually made things worse.

:Cueball: Maybe we should try to give ''bad'' advice?
:Ponytail: I guess it's worth a shot.

:Security tips
:(Print out this list and keep it in your bank safe deposit box.)
* Don't click links to websites
* Use prime numbers in your password
* Change your password manager monthly
* Hold your breath while crossing the border
* Install a secure font
* User a 2-factor smoke detector
* Change your maiden name regularly
* Put strange USB drives in a bag of rice overnight
* Use special characters like & and %
* Only read content published through Tor.com
* Use a burner's phone
* Get an SSL certificate and store it in a safe place
* If a border guard asks to examine your laptop, you have a legal right to challenge them to a chess game for your soul.

{{comic discussion}}

Talk:1525: Emojic 8 Ball

2015-05-15T06:46:57Z

141.101.98.172:

I'm not sure that "This is an obvious parody" counts as an explanation of the cartoon. I looked up "Magic 8 ball" (with which I was unfamiliar). I looked up "Emoji" (with which, too, I was unfamiliar). I then turned back to the cartoon, and I still don't understand it. What's more, there is no explanation of the practically unique absence of mouseover text. [[User:BinaryDigit|BinaryDigit]] ([[User talk:BinaryDigit|talk]]) 05:55, 15 May 2015 (UTC)
: Lack of mouseover / alt and title attributes is common in **interactive** comics. --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 06:23, 15 May 2015 (UTC)

It seems that this comic may be poking fun at the reliance of the modern generation on emoji for communication. By trying to answer serious questions only in emoji, their inadequacy in conveying information is shown. After all, a telephone and party ball hardly answer how one will die. It's all left to the imagination.
[[Special:Contributions/173.245.56.179|173.245.56.179]] 06:01, 15 May 2015 (UTC)

There might be a horoscope component to it too, i.e. you can interpret the emoji as a meaningful answer no matter which one you get. [[Special:Contributions/108.162.215.162|108.162.215.162]] 06:30, 15 May 2015 (UTC)

I'm guessing Randall is using Unicode emoji characters, i.e. from a font I don't have. I get a small rectangle with "01F40C" (two rows of three characters), which is indicative of "A character I have no font support for", in the browser I'm using (although from previous experience it isn't a browser thing, it's that I haven't deliberately installed the specialist font involved). Which rather spoils things for me, this time round, but I suppose doesn't cause problems for most people who have been persuaded to install emoji-characters to use in the place of 'mere' emoticons... [[Special:Contributions/141.101.98.213|141.101.98.213]] 06:36, 15 May 2015 (UTC)

1525: Emojic 8 Ball

2015-05-15T06:45:07Z

141.101.98.172: /* Explanation */

{{comic
| number = 1525
| date = May 15, 2015
| title = Emojic 8 Ball
| image = emojic 8 ball.png
}}

==Explanation==
{{incomplete|New page}}
This is an interactive comic. You can experience it by going to the xkcd site at http://xkcd.com/1525/ .

Emojic 8 Ball is a type of parody of {{w|Magic 8 Ball}} using {{w|emoji}} instead of words. Whereas the real Magic 8 Ball is shaken while you ask it a question and gives out an answer along the lines of YES or NO or ASK AGAIN, this comic takes written user input and once submitted gives a non-verbal answer using graphical {{w|Unicode}} "text" called emoji.

It is possible that this may be commentary on the inclusion of such "meaningless" symbols into Unicode. Ask a question and get a meaningless reply. Even more meaningless than the answers given by a Magic 8 Ball.

==Transcript==
{{incomplete transcript}}

{{comic discussion}}


[[Category:Interactive comics]]

1524: Dimensions

2015-05-13T07:24:28Z

141.101.98.172: /* Transcript */

{{comic
| number = 1524
| date = May 13, 2015
| title = Dimensions
| image = dimensions.png
| titletext = I would say time is definitely one of my top three favorite dimensions.
}}

==Explanation==
{{incomplete|Page created}}
==Transcript==
:[Cueball is sitting up against a tree, Megan lies with her hands behind her neck in front him under the foliage of the tree.]
:Cueball: Of the four dimensions I could have spent my life being pushed inexorably forward through, I guess "time" isn't the worst.

{{comic discussion}}



[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]

103: Moral Relativity

2015-05-01T11:16:25Z

141.101.98.172: /* Explanation */

{{comic
| number = 103
| date = May 17, 2006
| title = Moral Relativity
| image = moral_relativity.jpg
| titletext = It's science!
}}

== Explanation ==
This comic pokes fun at {{w|moral relativism}}, a philosophy in the field of {{w|ethics}} which holds that moral judgments are not absolute, but rather vary depending on the circumstances involved and the person (or people) committing it. Randall jokes about moral relativism by comparing it to the {{w|theory of relativity}} and creating a new related philosophy called "Moral Relativity." The scientific theory of relativity predicts (among other things) that measurements of an object change the closer to the speed of light it travels—length contracts, observed time slows down, the notion of separated simultaneous events is relative, etc. The graph is a parody on that of the {{w|Lorentz factor}}, which is the factor by which time is dilated and length contracted. It is humorous that the ethics of a situation would be relative the same way physical properties change as the speed of light is approached. This variation in ethics cited to explain why rap music, perhaps particularly {{w|Gangsta rap}}, which often has lyrics describing rape, murder and substance abuse, is better when travelling at speed.

Note that '''relativity''' in Theory of Relativity (in ''physics'') came from {{w|principle of relativity}} idea that equations describing the laws of physics have '''the same form''' in all admissible frames of reference (as opposed to ''moral'' relativity).

==Transcript==
:[A graph, rationalization as a function of speed, increasing asymptotically at ''c''.]
:Related to moral relativism, it states that ethics become subjective only when you approach the speed of light.
:That is, it's okay to be self-serving, steal, and murder as long as you're going really, really fast.
:(Note: This is why rap sounds better on the highway at 90 mph)

{{comic discussion}}
[[Category:Charts]]
[[Category:Philosophy]]
[[Category:Physics]]

Talk:1518: Typical Morning Routine

2015-04-29T06:06:36Z

141.101.98.172:

If he has hair, shouldn't he be called Hairy by definition?
Sidenote: Did I really just use the word whence?[[Special:Contributions/199.27.130.228|199.27.130.228]] 05:57, 29 April 2015 (UTC)

Added first draft for the transcript. This is my first edit here, so feel free to clean it up. [[Special:Contributions/173.245.56.158|173.245.56.158]] 06:02, 29 April 2015 (UTC)

I think that this is still Cueball because his hair isn't a different colour to his head. The only reason we can see it is because it's bed hair, and he hasn't combed it down yet. [[Special:Contributions/141.101.98.172|141.101.98.172]] 06:06, 29 April 2015 (UTC)