explain xkcd - User contributions [en]

Talk:3208: SNEWS

2026-02-17T21:11:42Z

Dkfenger: Comment on sucrose yield

The title text SNEWS is a reference to {{w|SuperNova_Early_Warning_System}}. {{unsigned ip|2a09:bac2:3656:ebe::178:123}} 21:58, 16 February 2026 (UTC)
: No, you're wrong. It stands for Southeast, North East West South, since those are the directions where it can detect them. - [[Special:Contributions/45.178.1.151|45.178.1.151]] 01:41, 17 February 2026 (UTC)

F1RST! also i posted this when there was no explanation. please fix this {{unsigned ip|2605:59c8:22e3:3e14:95a1:c5da:4c49:c384|22:55, 16 February 2026 (UTC)}}

Is this my mediocre non-native English, or should the title text read "setting off fireworks indoors"? (Trivia?) --[[Special:Contributions/2001:A62:5F7:FB01:538E:3F07:C9F0:F0C0|2001:A62:5F7:FB01:538E:3F07:C9F0:F0C0]] 23:06, 16 February 2026 (UTC)
:Yeah, 'setting of fireworks indoors, ...' would mean setting them up (i.e., placing them) and not 'setting off', lighting or detonating the fireworks. [[User:Sameldacamel34|Sameldacamel34]] ([[User talk:Sameldacamel34|talk]]) 23:22, 16 February 2026 (UTC)
:You can talk of setting explosives (the setting of them, as passively ready, to make them ready for later "setting them off"), so I expect the "setting of fireworks" is pretty much the same thing, much as with the setting of an alarm clock.
:Though also sounds like a possible americanism, like "lit it on fire" (c.f. my own prefered "set light to it"), if only because the former seem tautilogical; and/or strangely long-winded, such as with "to burglarize" vs. just "to burgle" (both being what a burglar does upon his burglary). But it's not one of those many funny transatlantic dialect things I've noticed previously, so I could be overexplaining what actually ''is'' merely a typo. [[Special:Contributions/82.132.239.3|82.132.239.3]] 01:33, 17 February 2026 (UTC)
::I could see it as a missing word "setting off of fireworks indoors" seems OK in American to me, though then I'd want a the: "The setting off of fireworks indoors"[[User:Lordpishky|Lord Pishky]] ([[User talk:Lordpishky|talk]]) 05:57, 17 February 2026 (UTC)

It snew [[User:Yaokuan ITB|Yaokuan ITB]] ([[User talk:Yaokuan ITB|talk]]) 23:28, 16 February 2026 (UTC)
:Exactly my thoughts, Yaokuan [[Special:Contributions/216.25.182.141|216.25.182.141]] 23:58, 16 February 2026 (UTC)
:Gesundheit! [[User:Logalex8369|Logalex8369]] ([[User talk:Logalex8369|talk]]) 01:35, 17 February 2026 (UTC)

Sorry, it somehow escaped me when editing the explanation that neutrinos have mass!! (even though we've known about this for decades). Does this mean that if the supernova is far away enough, the photons will arrive before the neutrinos? Or is that threshold too far to matter? [[User:Sameldacamel34|Sameldacamel34]] ([[User talk:Sameldacamel34|talk]]) 01:21, 17 February 2026 (UTC)

: Yes, but the threshold is too far away to have happened yet. Supernova neutrinos have [https://en.wikipedia.org/wiki/Supernova_neutrinos 10^10 to 10^20 MeV]. Judging by the table at the [https://en.wikipedia.org/wiki/Measurements_of_neutrino_speed Overview on neutrino speed], assuming we are about right about the mass of a neutrino, neutrinos that energetic would be traveling within a factor of 10-42 of ''c'', so they would need to have traveled for "a few"×1042 light hours, or a few 1038 years for the photons to catch up. Since the universe is less than 1.4×1010 years old, it'll be another few 1038 years until that happens. [[User:DoSnews|DoSnews]] ([[User talk:DoSnews|talk]]) 03:46, 17 February 2026 (UTC)
::Ah, interesting. And at that distance, the supernova would have to be unimaginably big to even notice/detect? Also, wouldn't it have to be far away enough that it would have traveled for so long the light gets redshifted into oblivion? [[User:Sameldacamel34|Sameldacamel34]] ([[User talk:Sameldacamel34|talk]]) 04:17, 17 February 2026 (UTC)
:::Since SN neutrino detections are tens of neutrinos an increase of even a few times the distances currently detected would render the neutrino pulse undetectable. And the optical event is stretched by time for the photons to migrate to the surface as well as glow from material heated by the explosion and decay heat from ejected material. If we consider only those photons from the explosion "lucky" enough to manage not to hit anything on the way out of the star/remnant they should arrive first by an undetectable time. Also, the explosion itself once triggered has to propagate across millions of miles of the stellar core so the explosion event is at least several seconds long.[[User:Lordpishky|Lord Pishky]] ([[User talk:Lordpishky|talk]]) 05:47, 17 February 2026 (UTC)
::Not 1010–1020, but 10–20. [[Special:Contributions/84.2.109.134|84.2.109.134]] 06:30, 17 February 2026 (UTC)
my first edit in almost 5 months i think lol [[User:Psychoticpotato|P?sych??otic?pot??at???o ]] ([[User talk:Psychoticpotato|talk]]) 01:45, 17 February 2026 (UTC)

One of the firework launchers on the device is aimed directly at the bed. [[User:Xkdvd|Xkdvd]] ([[User talk:Xkdvd|talk]]) 03:06, 17 February 2026 (UTC)
:Is it? Hard to tell in a 2d drawing... --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 07:11, 17 February 2026 (UTC)

"Ponytail is showing Hairy her bedroom." is the most hilariously euphemistic explanation of what's going on. [[Special:Contributions/82.13.184.33|82.13.184.33]] 09:24, 17 February 2026 (UTC)

Contrary to the current explanation, a foe is *exactly* equal to 10^44 joules, by definition. 1 erg is 10^-7 J and 1 foe is 10^51 erg. Also, I feel there is a [Citation required] somewhere in the section about the dangers of indoor fireworks. (Not happy about having to run Google's Javascript and helping train their image recognition algorithms on unfamiliar foreign street scenes in order to post here.) [[Special:Contributions/78.33.10.10|78.33.10.10]] 11:22, 17 February 2026 (UTC)
:I took it as being that while a foe is exactly that many joules (being a cm/g/s system derivative, not a m/kg/s one), neither a foe nor the equivalent value in joules are exactly the size of that which we might call a 'foe event', for which it was coined. But might have needed rewriting, as with the whole page (loads of little paragraphs and additions to paragaphs, now, at least needs more sensible reordering/grouping of facts and conjectures). [[Special:Contributions/82.132.239.216|82.132.239.216]] 11:58, 17 February 2026 (UTC)

I'll take the slightly disturbing take that Ponytail would rather die than miss a supernova, hence the fireworks [[User:SevenTheGamingKitty|SevenTheGamingKitty]] ([[User talk:SevenTheGamingKitty|talk]]) 19:46, 17 February 2026 (UTC)

The combustion number for sucrose is wrong. Heat of combustion is 1350kCal/mole, mass per mole is 342g, so you'd need about 2.5kg of sugar, not 0.6 grams. [[User:Dkfenger|Dkfenger]] ([[User talk:Dkfenger|talk]]) 21:11, 17 February 2026 (UTC)

Talk:2950: Situation

2024-06-24T23:11:09Z

Dkfenger:

For reference, the bridge in question is the Tacoma Narrows Bridge. [[User:Trimeta|Trimeta]] ([[User talk:Trimeta|talk]]) 18:57, 24 June 2024 (UTC)
:Noting that in all cases ''except'' the Tacoma Narrows, the design flaws were but a part of the issue, with operational decisions at the time playing a big part in the designed-in risks becoming reasons for an actual incident. The bridge could never have been "run safely", once built, unlike trying to ignore bunker fires whilst speeding through iceberg-alley or conducting stress tests in parallel with other non-standard procedures or just not refusing to conduct flights under certain weather conditions. Yes, the other things, by skipping the 'bad end' they actually had, would still be susceptible to future incidents (lessons not now having been properly learnt, or even known to be learnable, so still liable to being mishandled).
:But the only thing that could have saved the Tacoma bridge was to have been so much more alert (and less 'amused') by Galloping Gerti and immediately rushed into developing the better analytical models that could lead to an expensive in-situ retrofit (as with the Millenium Bridge, across the Thames, though that didn't have unavoidable wind issues and ''could'' be managed 'at leisure', whilst being made safer). And, without the rather spectacular demonstration of failure, it was probably not on the cards to 'not do nothing', even if it wasn't already too late to avert history in any reasonable way.
:It's human hubris/failings (at various levels) in each case, of course. But operational and design-time errors do more damage in combination than either by themselves. (Case in point, no deaths from the bridge collapse... actually handled pretty well, considering.) [[Special:Contributions/172.70.162.186|172.70.162.186]] 22:00, 24 June 2024 (UTC)

And for the record, the Challenger engineers *did* warn about the O-ring risk, but were overridden by management. [[Special:Contributions/172.68.35.95|172.68.35.95]] 19:25, 24 June 2024 (UTC)

It would have been so easy to draw a dam about to burst just behind the ocean liner {{unsigned ip|172.70.43.54|20:22, 24 June 2024}}
:Any particular dam-burst? There are many, but I'm not sure that we have an 'iconic' one... There's perhaps Taum Sauk, Vajont Dam, Brumadinho dam, El Cobre, Uttarakhand, Dale Dike Reservoir or Derna, picking a selection of notable ones. You couldn't count the deliberate Operation Chastise breaches or the (probably-)deliberate Kakhovka Dam one, nor all those 'nearly a disaster' ones (like Ulley and Toddbrook, two relatively recent concerns in the UK). [[Special:Contributions/172.70.162.186|172.70.162.186]] 22:00, 24 June 2024 (UTC)

Winds caused by maintenance on a nuclear reactor... What? [[Special:Contributions/172.69.208.173|172.69.208.173]] 22:46, 24 June 2024 (UTC)

Calling what leaked from the O-ring 'fuel' somewhat understates the issue. The O-ring failure let the SRB rocket exhaust itself burn through and damage the attachment strut and the external tank. [[User:Dkfenger|Dkfenger]] ([[User talk:Dkfenger|talk]]) 23:11, 24 June 2024 (UTC)

Talk:2941: Cell Organelles

2024-06-04T01:19:02Z

Dkfenger:

I'm a little disappointed there isn't a continuous endoplasmic reticulum with a zigzag in it.
Rogue mathematician away [[Special:Contributions/172.71.154.77|172.71.154.77]] 19:20, 3 June 2024 (UTC)

Sorry about the edit conflicts, attempting to fix.... [[Special:Contributions/108.162.245.237|108.162.245.237]] 20:12, 3 June 2024 (UTC)

Re [https://www.explainxkcd.com/wiki/index.php?title=2941:_Cell_Organelles&diff=343629&oldid=343628] is LLM use forbidden? I recall we have several ChatGPT-authored explanations, and had an ongoing discussion back when it was new. In any case, I've proofread and vouch for it, so I'm replacing the text. I encourage anyone who's bothered by it to paraphrase instead of delete. [[Special:Contributions/108.162.245.237|108.162.245.237]] 21:22, 3 June 2024 (UTC)

:If you've got the time to check AI-generated content properly and agree that it's what ''you'' would have written, you've got time to write it from scratch exactly how you'd have written it. And you get dangerously close to just putting in AI-content without checking at all, which right now is remains foolhardy.
:But, most of all, anything anyone submits can be changed by anyone else, and I don't know who picked up on it being AI and dealt with it the way they did, but only consensus can truly resolve where any attempt to impose an edit leads. [[Special:Contributions/162.158.74.119|162.158.74.119]] 22:36, 3 June 2024 (UTC)

::I almost completely agree with you for Wikipedia (I'd just change 'would' to 'could') and similar wikis, but it's undeniable that ExplainXkcd is different in some very substantial and obvious ways, many of which bear on whether to utilize AI. In particular, I would accept pretty much anything that helps explain the comic whether authored by human, machine, animal, or alien, but not hesitate for a second to, as the text below the Summary text input box says, edit it "mercilessly" whether I thought it was LLM-generated or not. But I wouldn't delete an even barely serviceable explanation ''just'' because I thought it came from an LLM, even if it was objectively low quality. I would try to improve it, which almost never means starting over from scratch. I'm not sure I believe the same is true for humans, who often insert, e.g., vandalism, trolling, or extremely undue and/or fringe topic passages. If an LLM is doing that, there's probably a human behind it. [[Special:Contributions/108.162.245.17|108.162.245.17]] 00:21, 4 June 2024 (UTC)

Re: the chloroplasts explanation: how do we know that this is an animal cell? (Would be good to say why...) -- [[User:Dtgriscom|Dtgriscom]] ([[User talk:Dtgriscom|talk]]) 22:18, 3 June 2024 (UTC)
:The cell has a membrane instead of a wall. [[Special:Contributions/162.158.90.199|162.158.90.199]] 22:24, 3 June 2024 (UTC)
::No, that’s human skin. [[User:Usb-rave|Usb-rave]] ([[User talk:Usb-rave|talk]]) 00:48, 4 June 2024 (UTC)

Why does Golgi look like an alien, he's so little and cute. Wtf. [[User:Psychoticpotato|Psychoticpotato]] ([[User talk:Psychoticpotato|talk]]) 23:11, 3 June 2024 (UTC)

Should 2732: Bursa of Fabricius be referenced? It feels like the Golgi Apparatus is making a similar joke, if somewhat inverted. [[User:Dkfenger|Dkfenger]] ([[User talk:Dkfenger|talk]]) 01:19, 4 June 2024 (UTC)

Talk:1725: Linear Regression

2016-08-26T17:10:22Z

Dkfenger: /* Teapot */ new section

== Teapot ==

It also seems likely that the teapot refers to the Utah Teapot (https://en.wikipedia.org/wiki/Utah_teapot). It was one of the first complex 3D objects defined for CGI rendering, and has seen countless uses since. Notably in the Pipes screensaver, and early SIGGRAPH papers where it was rendered along side the 5 platonic solids as if it belonged with them.
[[User:Dkfenger|Dkfenger]] ([[User talk:Dkfenger|talk]]) 17:10, 26 August 2016 (UTC)