explain xkcd - User contributions [en]

3049: Incoming Asteroid

2025-02-11T04:51:38Z

172.69.33.190: /* List of sizes and consequences */

{{comic
| number = 3049
| date = February 10, 2025
| title = Incoming Asteroid
| image = incoming_asteroid_2x.png
| imagesize = 454x570px
| noexpand = true
| titletext = The bottom ones are also potentially bad news for any other planets in our solar system that have been counting on Earth having a stable orbit.
}}

==Explanation==
{{incomplete|Created by an incoming bearer of bad news - More accurate readings of the log scale, and provide detailed explanations of each point on the chart (should probably be a table, as well). Do NOT delete this tag too soon.}}

This comic may be inspired by the recent discovery of asteroid {{w|2024 YR4|2024 YR4}}, which is estimated to have about a 2% chance of striking Earth on December 22, 2032. Its size is estimated to be 40-90 meters.

This comic provides a log scale correlating the size of any incoming asteroid to whether its arrival is good or bad news. While asteroids on the smaller end of the scale are good news for sky watchers, as the upcoming objects get bigger, the potential for catastrophe grows. Many astronomy enthusiasts would be happy to see bigger meteors, as bigger generally means more exciting pictures. Of course, once the meteors grow past a certain size even the most enthusiast astronomer might grow concerned about their imminent extinction.{{cn}}

===List of sizes and consequences===
Sizes are approximate.

* '''1 cm''': Good news! Meteors are pretty!
** At this size, such a meteor is nothing more than a streak in the sky.

* '''30 cm''': Great news! You might see a fireball!
** At this size, a meteor might descend far enough for the flames of its entry to be visible with the naked eye.

* '''3 m''': Okay news, unless you have expensive windows or are very unlucky
** At this side, a meteor can expect to descend far enough for the shockwave of its passing to shatter windows. The comic mockingly claims this is only a problem if your windows are expensive or happen to get directly hit by it.

* '''100 m''': Bad news, especially if you live near the city it's aimed at
** The {{w|Tunguska event|Tunguska meteor}}, which flattened over 2,000 km2 of Siberian forest in 1908, was 50-60 m across.

* '''1 km''': Bad news, especially if you live on the continent it's aimed at
** Meteors of either size can easily cause localized extinction, and can be expected to have effects on the rest of the world as well.

* '''6 km''': Bad news for your species.
** The {{w|Chicxulub crater|Chicxulub asteroid}} that wiped out non-avian dinosaurs was about 10 km in diameter.

* '''50 km''': Bad news for your phylum.
**{{w|Chordate|Our phylum}} is primarily all the vertebrate animals.

* '''200 km''': Bad news for your biosphere
** For meteors of this size, a global extinction event is pretty much guaranteed.

* '''3,000 km''': Good news for any life that might some day evolve on Earth's new moon
** Earth's moon is believed to have been formed when Earth, in its infancy, was hit by an object of roughly this size. The comic assumes that another moon would form from another such impact, hypothesizes that life might evolve on that moon, {{tvtropes|BadNewsInAGoodWay|and pretends that it's good news}}.

* '''30,000 km''': Bad news for whatever planet is about to get hit by Earth.
** At this size, the "asteroid" is larger than Earth itself (whose diameter is about 12,700 km) and would likely be classified as a planet. (Unofficially, at least. ''Officially,'' there would be quibbling about whether it had "cleared its orbit." Briefly. {{Citation needed}}) At that point, the comic points out, it would be more accurate to describe the Earth crashing into the "asteroid"/planet, not the other way around.

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

:[Header:]
:An asteroid is headed straight for Earth! That's...

:[A log scale of lengths is shown, labelled "Asteroid size", with markings of 1 cm, 10 cm, 1 meter, 10 meters, 100 meters, 1 km, 10 km, 100 km, 1,000 km, and 10,000 km. The remaining lines of text are at various points down the scale.]
:...Good news! Meteors are pretty!

:...Great news! You might see a fireball!

:...Ok news, unless you have expensive windows or are very unlucky.

:...Bad news, especially if you live near the city it's aimed at.

:...Bad news, especially if you live on the continent it's aimed at.

:...Bad news for your species.

:...Bad news for your phylum.

:...Bad news for your biosphere.

:...Good news for any life that might someday evolve on Earth's new moon.

:...Bad news for whatever planet is about to get hit by Earth.

{{comic discussion}}

[[Category:Charts]]
[[Category:Astronomy]]
[[Category:Space]]

Talk:3046: Stromatolites

2025-02-04T19:07:26Z

172.69.33.190:

Yay, another Beret Guy appearance! '''[[User:42.book.addict|42.book.addict]][[User talk:42.book.addict|Talk to me!]]''' 03:46, 4 February 2025 (UTC)

I'm not sure if I'm trying to remember Bloom County and the penguin (Opus) or Snoopy by Schulz because of the last panel. Shrug. Prolly both. Warm is good. [[Special:Contributions/172.70.175.208|172.70.175.208]] 06:08, 4 February 2025 (UTC)
:Add Zonker to this list? [[Special:Contributions/108.162.245.39|108.162.245.39]] 17:29, 4 February 2025 (UTC)
:: Zonker Harris, yes! [[Special:Contributions/172.70.175.106|172.70.175.106]] 18:16, 4 February 2025 (UTC)

How can anybody be related to rock formations? Stomatolites are not organisms, they are the product of organisms. [[Special:Contributions/141.101.105.88|141.101.105.88]] 08:12, 4 February 2025 (UTC)
:This might be one of Randall's weaker offerings in terms of scientific accuracy. I think that "stromatolites" as here used refers to the cyanobacterial component of stromatolites, which is the component detected in ancient fossils and is the one responsible for oxygen-evolving photosynthesis (responsible for what was perhaps the {{w|Great_Oxidation_Event|first global environmental catastrophe}} - an element of ancestry of which it might be wise not to boast). Modern stromatolites have both cyanobacteria (ancestors of plastids) and alpha-proteobacteria (ancestors of mitochondria) in their microbial mats, and it's reasonable to assume that alpha-proteobacteria were present in the fossils. So the "cousins" would be of cyanobacteria in the stromatolites, not the stromatolites themselves (in which both were, presumably, cohabiting). Beret Guy also appears to be confused about the proposed sequence of events leading to the origins of mitochondria and eukaryotic cell nuclei. [[Special:Contributions/108.162.245.39|108.162.245.39]] 17:29, 4 February 2025 (UTC)
:I've seen the surviving microbial mats in Australia referred to as "stromatolites" as well.[[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 12:39, 4 February 2025 (UTC)

I wonder if he is related to any specific dinosaurs or whether he bypassed that branch of the tree completely. 09:48, 4 February 2025 (UTC)

I think there's a joke (or at least a reference) here about the relatedness of life. All currently-known organisms are related by descent from a common ancestor, which in English makes us all cousins, of various distances. Mitochondria in plants and animals, for instance, must descend from the same bacterium-like organism that became an endosymbiont in a proto-eukaryote.[[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 12:39, 4 February 2025 (UTC)
:Since mitochondria and chloroplasts were both originally distinct organisms that were absorbed into the host cells, that makes most modern life descendants of cannibals. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:37, 4 February 2025 (UTC)
::By that logic, eating pretty much any food except salt (and maybe dairy?) is cannibalism. [[Special:Contributions/172.68.70.87|172.68.70.87]] 16:09, 4 February 2025 (UTC)

I immediately thought of [https://fabpedigree.com/ Fabulous Pedigree], which ''does'' include ancestry (and side-branches) going back to (and past) mitochondria, though from a quick check it doesn't seem to specifically include stromatolites. Obviously the listing has lots of (mostly implied) gaps. --[[Special:Contributions/162.158.217.72|162.158.217.72]] 13:55, 4 February 2025 (UTC)

Beret Guy is emulating Pooh-Bah in The Mikado: "I can trace my ancestry back to a protoplasmal primordial atomic globule."[[Special:Contributions/172.69.33.190|172.69.33.190]] 19:07, 4 February 2025 (UTC)NickM

== The [[What If? chapters|What If? article index]] project ==

Hey everyone,

I'm not sure if you noticed the banner of the site, but for the last few weeks a group of [[Talk:What If? chapters|incredibly talented editors]] have been redesigning the [[What If? chapters|'''index of ''What If?'' articles''']] from the ground up. Among other things, we've merged two huge tables, added a TON of additional info, created complex templates, and made [[What If? chapters|dozens and dozens of other improvements]]. I believe that, as a wiki, we should have a complete and detailed index of all what if? articles, [[List of all comics (full)|just like we do for the comics]], and we're getting so close to that goal! We mostly only need to add the missing explanations, improve the existing ones, and add the questions and answer summary from the books (plus other things).

We would love your help (especially if you have the first book)! We've prepared a [[What If? chapters|to-do list]] at the top of the page, containing everything that needs to be done, if you're interested. --[[User:FaviFake|FaviFake]] ([[User talk:FaviFake|talk]]) 07:00, 4 February 2025 (UTC)

==Clicking and clicking and clicking==

I've added a bit about the length of time it would need to take to click that far back in the past. I'm sure I have got the amount out by several orders of magnitude, so I would appreciate it if anyone fancies a go at estimating how long Beret Guy would have taken. [[Special:Contributions/172.71.241.27|172.71.241.27]] 10:49, 4 February 2025 (UTC)

Talk:657: Movie Narrative Charts

2024-12-24T00:57:20Z

172.69.33.190:

...but in 12 Angry Men, at two points, some of the jurors leave to -- and have conversations in -- the bathroom! {{unsigned ip|‎193.25.222.71}}

Luke went to Endor, right?[[Special:Contributions/108.162.210.172|108.162.210.172]]

Why is this not part of the explaination? http://en.wikipedia.org/wiki/File:Minard.png

It is public domain so it should be allowed right? [[Special:Contributions/108.162.246.117|108.162.246.117]] 03:43, 10 March 2014 (UTC)

I added it to the explaination as it certainly adds to the understadning of the comic. It was already uploaded by someone else. [[Special:Contributions/108.162.246.117|108.162.246.117]] 03:50, 10 March 2014 (UTC)

Only flaw is that Saruman died at the wrong time. [[User:LordSamanon|LordSamanon]] ([[User talk:LordSamanon|talk]]) 02:03, 4 March 2015 (UTC)

Second flaw is that Sam is going to west, too {{unsigned ip|141.101.99.80}}

: But much later, as does Legolas together with Gimli. Both Aragorn and Arwen's deaths are also in the last book but not shown here. All these events just happen way after the main story and are thus not included in the chart. Btw., Wormtongue also only dies later, around the time Saruman actually dies (in fact, he's the one who murdered Saruman). [[Special:Contributions/108.162.229.18|108.162.229.18]] 14:32, 3 January 2021 (UTC)

Third flaw is that in 12 Angry Men, Juror 8 interacts with Juror 9 at the very end.{{unsigned ip|108.162.215.56}}

I figured it would be of interest of the people here that I have gone through the afford of making one of these as well. It took me a few hours, but I am quite proud of the final image. It's definitely not perfect, though, and I am sure it could be done much better (especially if Randall himself would do it ;)). Either way, here is a movie narrative chart for the first ''Pokémon'' film, ''Mewtwo Strikes Back'', something I grew up with and felt worked pretty well in this form: http://maplestrip.tumblr.com/image/123162717416 [[User:Maplestrip|Maplestrip]] ([[User talk:Maplestrip|talk]]) 18:58, 4 July 2015 (UTC)

I doubt that it's really worth including in the explanation or anything, but it would seem that Grant's and Sattler's lines get swapped by the first time their names are reiterated. --[[Special:Contributions/108.162.242.134|108.162.242.134]] 13:18, 14 January 2016 (UTC)

: You're right! Perhaps this could be also mentioned in a "mistakes" / trivia section, as the flaws above. --[[User:LaVe|LaVe]] ([[User talk:LaVe|talk]]) 13:59, 24 February 2017 (UTC)

For me it is SO weird that this is today's Incomplete Explanation. Yesterday on Facebook, I had a Memory that I shared this 1 year ago today (so, 1 year ago yesterday). :) - NiceGuy1 [[Special:Contributions/162.158.126.76|162.158.126.76]] 04:31, 4 January 2017 (UTC) I finally signed up! This comment is mine. [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 05:35, 9 June 2017 (UTC)

I added some transcript. I didn't manage to use different colors in the transcript, so I added the HEX-Codes directly in the text. I'm not mother-tongued so please correct if you find mistakes. --[[User:LaVe|LaVe]] ([[User talk:LaVe|talk]]) 12:30, 20 February 2017 (UTC)
:Cool with the transcript. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 18:20, 24 February 2017 (UTC)
::Hey [[User:Kynde|Kynde]], we've talked about transcripts. Someone reading the text should understand the picture; not each pixel. I've also talked to [[User:LaVe|LaVe]] and I promised that I will work on this soon. Stay tuned...--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 19:47, 24 February 2017 (UTC)

I added to the star wars section. Not to familiar with Jurassic Park so an someone add to that and complete the transcript so this comic is complete?[[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 23:31, 2 March 2017 (UTC)

i clicked on the incomplete explanation in the spotlight link to see if i could fix it
...
some comics will not and should not ever be fully explained [[Special:Contributions/108.162.226.101|108.162.226.101]] 04:10, 23 March 2017 (UTC)

HOW is this still not complete, it looks pretty good to me. Just want more opinions.[[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 19:42, 12 April 2017 (UTC)

:It certainly wants a much better discussion of ''Napoleon's March'' which is hard to do without the image. I asked on the noticeboard for someone to upload it ([[Admin_requests#Minard.27s_map_for_657]])...Or I guess i could artificially up my post-count and then wait a week... [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 22:46, 12 April 2017 (UTC)
::The explanation of the Minard map on the linked page seems adequate. Not every piece of information needs to be in this wiki.[[Special:Contributions/108.162.245.136|108.162.245.136]] 03:19, 18 April 2017 (UTC)
:::I would disagree. Most people don't follow links. I would say that the Minard map is absolutely essential to understanding this comic. All of the images in the comic are based on the Minard map, and if you haven't seen the Minard map, you haven't understood the comic. Reasonably people can disagree on that, of course, but I think it unquestionably passes the "relevance" test that you mention ("Not every piece of information needs to be in this wiki"). An appropriate contextual explanation needs to be written. That's on my todo list after the image is working, which it is not right now. [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 03:40, 18 April 2017 (UTC)
:::: Hey, are we sure it's a "reference" though? I wouldn't be surprised if it is, but I also wouldn't be surprised if Randall just thought this up. Has he credited the Minard map with inspiring this comic? --- S
::Nice work on the pic, I moved it so that the text is above the picture. It makes more sense for readers to read the text for background knowledge and then see the pic.[[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 20:11, 19 April 2017 (UTC)
:::At the risk of excessive navel-gazing, I wonder if we're better off putting it on the right with the text accompanying it on the left. Also maybe shrinking it a bit more. I dunno... [[User:JohnHawkinson|JohnHawkinson]] ([[User talk:JohnHawkinson|talk]]) 03:07, 20 April 2017 (UTC)
:::: There are many comics where there is a pic in the middle,see [[1282: Monty Hall]] just need a little more opinion. [[User:Dontknow|Dontknow]] ([[User talk:Dontknow|talk]]) 23:10, 20 April 2017 (UTC)

I am not sure if this should be included, but it is a nice piece of trivia anyway: Randall seems to have inspired a whole field of research in digital humanities with this strip. There are now multiple papers on "storyline visualizations" that reference this comic, using the concept for visualizations of storylines, politic events and other stuff. https://link.springer.com/chapter/10.1007/978-3-319-50106-2_30 {{unsigned|162.158.88.128|11:06, 20 October 2017 }}

It is a fascinating concept. Not gonna lie, I could 100% spend the rest of my life making these charts. --- someone who's not smart enough to type all those brackets [[Special:Contributions/172.69.33.172|172.69.33.172]] 07:18, 10 December 2024 (UTC)

2985: Craters

2024-09-14T01:33:56Z

172.69.33.190: /* Explanation */

{{comic
| number = 2985
| date = September 13, 2024
| title = Craters
| image = craters_2x.png
| imagesize = 457x352px
| noexpand = true
| titletext = It's annoying that the Nastapoka Arc isn't a meteor impact crater, but I truly believe that--with enough time, effort, and determination--we could make it one.
}}

==Explanation==
{{incomplete|Created by a LITTLE PRINCE ON A ROCK - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic uses a Venn diagram to classify large circles on the ground into meteor impact craters, "weird circles on the map", and both.

{| class=wikitable
! scope="col" | "Crater"
! scope="col" | Venn diagram section
! scope="col" | Explanation
|-
|Northern {{w|Yucatan Peninsula}}|| Meteor Impact Craters || This refers to the famous {{w|Chicxulub crater}}, where an asteroid ~10 km in diameter struck the Earth 65 million years ago and caused the extinction of non-avian dinosaurs.
|-
|{{w|Charlevoix impact structure|Charlevoix Region}}||Meteor Impact Craters|| Astroblème de Charlevoix, or Charlevoix impact crater. A 400 million-year-old, 54 km-wide crater which lies partly in the waters of the {{w|St. Lawrence River}} and stretches halfway between {{w|Quebec City}} and the mouth of the {{w|Saguenay River}}.
|-
|{{w|Sudbury Basin}}||Meteor Impact Craters||
|-
|{{w|Chesapeake Bay}}||Meteor Impact Craters||
|-
|{{w|Manicouagan Reservoir|Lake Manicouagan}}||(Venn diagram intersection)||
|-
|{{w|Lonar Lake}}||(Venn diagram intersection)||
|-
|{{w|Clearwater Lakes}}||(Venn diagram intersection)||
|-
|{{w|Meteor Crater}}||(Venn diagram intersection)||A crater in Arizona about 1.2 km across where a meteor hit around 50,000 years ago.
|-
|{{w|Nastapoka Arc}}||Weird Circles on the Map|| A section of the shoreline of southeastern Hudson Bay that's almost a perfect circle.
|-
|{{w|Crater_Lake_(disambiguation)|Crater Lake}}||Weird Circles on the Map||Most likely reference is the {{w|Crater Lake}} that's in Oregon, the deepest freshwater body in the United States, which formed in the {{w|caldera}} of {{w|Mount Mazama}} after it exploded around 7700 years ago.
|-
|{{w|Stonehenge}}||Weird Circles on the Map||{{w|Stonehenge}} is a {{w|megalith}} on the {{w|Salisbury Plain}} in England which is famous not only for its historical significance and impressive scale but for {{w|Theories_about_Stonehenge|stories surrounding its creation and purpose}}.
|-
|The {{w|Great Blue Hole}}||Weird Circles on the Map||A large, nearly-circular {{w|Blue hole|marine sinkhole}} off the coast of {{w|Belize}}.
|-
|Delaware's northern border||Weird Circles on the Map||The {{w|Twelve-Mile Circle}} comprises several surveyed arcs that define the borders between Delaware and Pennsylvania, and between Delaware and bits of Maryland and New Jersey. These arcs and Stonehenge are the only manmade features in this comic.
|}

The title text refers to the {{w|Nastapoka Arc}}, a section of the Hudson Bay shoreline that is almost a perfect circle. This was most likely caused by continental plates crashing into each other rather than a meteor impact. However, Randall believes that it CAN be an actual meteor impact site with enough dedication: he wants to redirect an asteroid into Hudson Bay, which is a bad idea{{Citation needed}}. There is no efficient way to artificially direct asteroids towards Earth, let alone ones large enough to make the appropriate size hole. The {{w|Double Asteroid Redirection Test}} (DART) slightly changed the orbit of one asteroid around another by slamming a spacecraft into the asteroid; doing any more substantial redirection would require placing explosives, which has never been done. Moreover, the precision required would be a massive obstacle: a small variance in timing or angle would make the asteroid hit Earth in the wrong place, creating an improperly shaped or sized hole, to say nothing of the risk of it missing entirely and slamming into populated areas. Attempting to do so would be costly{{Citation needed}} and potentially cause massive devastation{{Citation needed}}.

This idea of directing an asteroid to directly impact the Earth is on some level an inversion of disaster movies like Armageddon, where an asteroid is landed on to destroy or deflect it. Armageddon has been discussed before on xkcd.

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

:[A Venn diagram with two circles.]
:[Label above left circle:]
:Meteor Impact Craters
:[Label above right circle:]
:Weird Circles on the Map
:[Left circle items (Meteor Impact Craters):]
:Northern Yucatan Peninsula
:Charlevoix Region
:Sudbury Basin
:Chesaspeake Bay
:[Right circle items (Weird Circles on the Map):]
:Nastapoka Arc
:Crater Lake
:Stonehenge
:The Great Blue Hole
:Delaware's Northern Border
:[Middle intersection items:]
:Lake Manicouagan
:Lonar Lake
:Clearwater Lakes
:Meteor Crater

{{comic discussion}}

[[Category:Venn diagrams]]
[[Category:Geology]]
[[Category:Geography]]

2971: Celestial Event

2024-08-14T16:59:19Z

172.69.33.190: /* Explanation */ wlink

{{comic
| number = 2971
| date = August 12, 2024
| title = Celestial Event
| image = celestial_event_2x.png
| imagesize = 471x300px
| noexpand = true
| titletext = If we can get a brood of 13-year cicadas going, we might have a chance at making this happen before the oceans evaporate under the expanding sun.
}}

==Explanation==
{{incomplete|Created by a CURSED SHOP THAT APPEARS EVERY FOUR POINT THREE BILLION YEARS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This comic was posted shortly after some people reported seeing the {{w|Aurora}} in conjunction with the {{w|Perseids meteor shower}}.<ref>https://www.msn.com/en-us/weather/topstories/the-2024-perseid-meteor-shower-and-northern-lights-overlapped-in-a-rare-cosmic-display-see-photos-of-the-dazzling-event/ar-AA1oJKKC</ref> It lists several events that are considered special to be witnessed due to their rarity. Total solar eclipses, auroras and comet sightings are all rare events. This year, all three of these events happened in parts of Massachusetts, United States, where the author lives.

Although it might be, conceivably, possible to witness all three at once in a given location (in this case, the author's neighborhood), the odds stack up to make that occurrence extremely improbable. To boot, those events can only be observed with a clear sky (a 50:50 chance), so that too has to be accounted for in the calculation.

"Total eclipse" presumably refers to total solar eclipses, as total lunar eclipses are visible from any side of the Earth that the Moon is visible. Using [https://eclipse.gsfc.nasa.gov/JSEX/JSEX-index.html this nifty tool from NASA], we can estimate the frequency of solar eclipses for a given location. For example, for the city of Boston, MA, there are 14 total solar eclipses in a 4500 year interval, an average of once every 320 years, which is close to the author's estimate. It must be noted that the author did not include annular eclipses, possibly because it would be harder to witness the aurora and the comet sighting during those. Also, unlike the other factors, the 1/350 implies that a total eclipse can be seen for the whole year, when in fact that variable would be (when generous) a mere hour every 350 years.

17-year {{w|Periodical cicadas|cicadas}} are also special in the sense that a brood will only emerge from the ground once every 17 years. Periodical cicadas recently became the object of media furor in 2024 as a 13-year brood and a 17-year brood happened to emerge together in parts of the US, an event that for the same two broods only happens once every 13x17 = 221 years. This caused a lot of noise and double the amount of dead cicadas after they had mated. Needless to say, having a cicada emergence co-occur with all those previously mentioned events would be extra rare, and thus extra special.

How rare, exactly, is the point of this calculation. The resulting product is the expected frequency that all of them would occur at the same time at that location. The value he calculates is once every 4.3 billion years. This is in the same ballpark as the current age of the Earth, about 4.5 billion years.

There are multiple inaccuracies in this type of calculation (though, given the extravagant nature of the proposed event and the unfeasible time scale, perhaps that hardly matters). Multiplying probabilities only works for random variables that are entirely independent. If nothing else, orbits are (luckily[maybe]) not random.{{Citation needed}} It also requires that all of the probabilities remain constant over time. In reality, cicadas will not exist for very long compared to the time scale, since Earth will become uninhabitable to complex life within a billion years' time and all life will be extinct within {{w|Future of Earth|4 billion years}}. Also, the Moon is moving away from Earth, and total solar eclipses will cease to occur in about [https://www.space.com/37627-total-solar-eclipse-earth-moon-alignment-future.html 600 million years]. Luckily, this is not the time that you are ''always'' going to wait, merely the (usual) period between one occurance and the next. A person starting to wait at a random point in the cycle, and not knowing anything else, would ''on average'' only have to wait ''half'' the time. (If very lucky, it could happen tomorrow, as it hypothetically might have done a bit over four billion years ago; if unlucky, it would indeed be slightly more than four billion years, having most recently happened yesterday; if ''very'' unlucky, the frequencies are slightly less defined, do not actually align as expected for the next conclusion of the cycle and additional billions of years need to be waited until the next example when it 'might' indeed occur as anticipated. Finally, if '''extremely''' unlucky, you will never get a clear sky. Ever.)

In order for the math to work out, some unit conversion is necessary. To solve "20 days / 11 years", one can consider 1 year = 365.25 days (a reasonable approximation that accounts for most leap years and is used in common {{w|Julian year (astronomy)|astronomical calculations}}). For "2 months / 50 years" and "2 months / 17 years", the simplest way is to convert 1 year into 12 months. Unit cancelation works out, and you end up with a number in years that corresponds to the average amount of time between events when all those different things are happening at once. (The implied unit for eclipses is events per year, and that's the unit you get as a result, so the actual length of the eclipse doesn't influence the result much.)

In the title text, Randall mentioned swapping 17-year cicada broods for 13-year ones, to have some chance at witnessing the proposed super-event before life on Earth becomes impossible. Massachusetts is near the northern limit of {{w|Periodical_cicadas|Magicicada}} distribution, and only one 17-year brood is established there (and not in Cambridge, MA). However, the introduction of a different brood could, with some help from global warming, be feasible. There are other variables that are possibly available for manipulation: clear skies can be arranged with various methods of {{w|Weather modification|weather control}}; special cicada broods may be bred or bioengineered specifically to coincide with the other factors of the celestial event; and while the aurora cannot currently be manipulated by humans, there may be artificial methods to make it possible.

Earth's oceans may evaporate in about one billion years<ref>https://www.sciencedaily.com/releases/2013/12/131216142310.htm</ref>. In order to beat that, we need to better our odds. Using 13-year cicadas in our calculations reduces the average interval between events to 3.29 billion years. We can lower that further by hoping that we'll have clear skies by then (who knows, we might get good enough at manipulating weather that we can *make* it happen). That gives us an average interval between events of about 1.6 billion years. Which means a larger than 50% chance that we'll get our special super-event to happen within a billion years, therefore beating ocean evaporation. Of course, cicadas still may not last that long.[baseless conjecture] [trust the cicadas]

===References===
<references/>

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Approximate frequency in my area

:Active northern lights: 20 days per solar cycle

:A naked-eye "Great Comet": 2 months every 50 years

:Total eclipse: once every 350 years

:Clear skies: 50% of the time

:17-year cicada emergence: 2 months every 17 years

opening bracket

20 days over 11 years multiplied by

2 months over 50 years multiplied by

1 over 350 years multiplied by

one half multiplied by

2 months over 17 years

closing bracket to the power of -1

equals 4.3 billion years

:[Caption below the panel:]
:Every 4 billion years or so, my neighborhood gets to see a ''really'' spectacular show.

{{comic discussion}}

[[Category:Astronomy]]
[[Category:Solar eclipses]]
[[Category:Time]]
[[Category:Animals]]

2967: Matter

2024-08-03T04:07:20Z

172.69.33.190: /* Explanation */ oxford comma

{{comic
| number = 2967
| date = August 2, 2024
| title = Matter
| image = matter_2x.png
| imagesize = 234x341px
| noexpand = true
| titletext = He was the first person to land a 900, which is especially impressive because pulling off a half-integer spin requires obeying Fermi-Dirac statistics.
}}

==Explanation==
{{incomplete|Created by a GOOFY FRONTSIDE WIKI GRIND TO SECRET PHYSICS DEMO TAPE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In {{w|skateboarding}}, the term 'goofy' means to use the {{w|Footedness#Goofy_stance|opposite stance}} of the 'standard-footed' one where one pushes with right foot. This comic takes this as an apparent analogy of {{w|antimatter}} in elementary physics, which exhibits the opposite charge to normal matter will mutually destroy 'normal' matter (releasing energy relative to the original mass). This appears to be the kind of explanation that one gets when {{w|Tony Hawk}}, an ex-professional skateboarder of great renown[https://www.mobygames.com/game/3567/tony-hawks-pro-skater/], is teaching.

This metaphor also indirectly raises the problem of {{w|baryon asymmetry}}, in which ordinary matter appears to be much more common than antimatter, unlike most{{citation needed}} distributions of handedness, chemical {{w|chirality}}, or the {{w|skewness}} of {{w|Multimodal_distribution|bimodal statistics}} describing asymmetries in nature (called {{w|homochirality}}, e.g., organ shape and centering, or plants favoring one branch over the other at a fork) and in artificial methods, while 'goofy-footed' skaters are about common as 'regular-footed'.

The use of Tony Hawk in the comic is could be a play on {{w|Stephen Hawking}}, a famous astrophysicist and professor at the University of Cambridge before his death in 2018. As Tony Hawk does not have a degree in physics{{citation needed}}, teaching popular but inaccurate versions is a likely pitfall of his professorship.

The title text describes Hawk as the first person to "land a 900," meaning the successful completion of a {{w|900 (skateboarding)|skateboarding trick}} involving two and a half rotations, or nine hundred degrees (2.5 × 360° = 900°). In physics, {{w|Spin (physics)|'spin'}} is a {{w|quantum number}} describing subatomic particles, named for the analogous ''but crucially distinct'' concept of {{w|angular momentum}} in classical physics. Obeying {{w|Fermi–Dirac statistics}} requires that the particles involved are {{w|fermion}}s, which include all of the electrons, protons, and neutrons comprising the entirety of Hawk's mass and electrochemical state. Fermions all have {{w|half-integer}} (i.e., ...-1½, -½, ½, 1½...) {{w|spin quantum number}}s which do indeed include 2½. However, it's very important to remember that [https://www.youtube.com/watch?v=pYeRS5a3HbE&ab_channel=ScienceClicEnglish quantum mechanical spin is ''not'' rotation, but how quickly the corresponding particle changes state when rotated.] In fact, all skateboarders, indeed all animals, plants, minerals and most everything we ever interact with ordinarily except light, cosmic rays, and their decay products, are comprised entirely of fermions, so everyone is forced to obey Fermi–Dirac statistics at all times. This is called the {{w|Pauli exclusion principle}}, and it's what gives mostly empty atoms the property of substance, allowing you to hold things, walk, make sound waves with your voice, and employ any mecanical property of matter.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Tony Hawk (drawn with short hair) gesturing at a narrow whiteboard on which illegible things are marked, what may be a Feynman diagram with one of the particle/antiparticle pair going into a circle (possibly representing a black hole, and thus depicting the popularized(incorrect) analogy for {{w|Hawking radiation}}), and at the bottom, a 2x3 table of values.]
:Tony Hawk: In the standard model, regular matter will annihilate if it comes in contact with oppositely-charged ''goofy'' matter.

:[Caption below the panel:]
:Tony Hawk becomes a physics professor

{{comic discussion}}

[[Category:Comics featuring real people]]
[[Category:Physics]]
[[Category:Statistics]]

Talk:2946: 1.2 Kilofives

2024-06-15T04:19:32Z

172.69.33.190:

Challenge: Come up with a way like this to say the comic number #2946. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 03:00, 15 June 2024 (UTC)
:How about 4.91 hectosixes? [[Special:Contributions/172.69.33.190|172.69.33.190]] 04:19, 15 June 2024 (UTC)

2371: Election Screen Time

2020-10-13T00:04:08Z

172.69.33.190: /* Transcript */ category

{{comic
| number = 2371
| date = October 12, 2020
| title = Election Screen Time
| image = election_screen_time.png
| titletext = Feels like I picked a bad year to try to start having a healthy relationship with political news.
}}

==Explanation==
{{incomplete|Created by ELECTION UPDATES. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

[[Cueball]] is looking at his phone, which informs him of time spent doing two activities: Staying updated about important election events (26m) and unimportant election events (9h14m). Both the wording on the phone and the title text suggest that too much time has been spent on trivial election minutiae.

This comic was probably created because of the upcoming {{w|2020 United States presidential election}} between the incumbent, President {{w|Donald Trump}} and the challenger, former Vice President {{w|Joe Biden}}.

The title text is referring to the wide amount of news coverage during this election season.

==Transcript==

[Cueball is looking at his phone screen time report. The screen appears above his head]

Screen Time Report
:Staying informed about politics like a good civic minded person
:..26m
:Reading election updates that won't affect your actions in any way but slightly improve your knowledge about what's going to happen in a few weeks
:.................................................9h14m

{{comic discussion}}
[[Category:Elections]]
[[Category:Comics featuring Cueball]]
[[Category:Phones]]