explain xkcd - User contributions [en]

Talk:893: 65 Years

2025-12-02T15:50:19Z

140.141.134.242:

I wonder if it would be possible to identify ''individual people'' who are behind those vertical jumps in the graph (in the not projected part)... --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 19:18, 14 December 2012 (UTC)
*Glad you asked! </Information Hen> Neil Armstrong and Buzz Aldrin landed in July 1969; that's two. Pete Conrad and Alan Bean joined the group that November; that's four. Alan Shepard and Edgar Mitchell in February '71; that's six. David Scott and James Irwin in July '71; that's eight. John W. Young and Charles Duke in April '72; that's ten. Eugene Cernan and Harrison Schmitt in December '72; that's twelve. Irwin died in '91, dropping it to 11. Shepard and Conrad died in '98 and '99 respectively, making it 9 as of the date this comic was published. Armstrong died in '12, so our current number is 8. The oldest living person to have landed on the moon is Aldrin, 83. There are two 82-year-olds, two 80s, one 78 and two 77s. [[User:Ekedolphin|Ekedolphin]] ([[User talk:Ekedolphin|talk]]) 13:28, 27 January 2013 (UTC)

Almost prophetic and very, very sad. RIP Neil Armstrong ------ {{unsigned ip|188.29.119.251|08:59, 31 December 2012 (UTC)}}

Can we add the 5% and 95% columns to the table? [[User:Spongebog|Spongebog]] ([[User talk:Spongebog|talk]])
::i dont feel like this would add to the explanation of the comic and would require us to know a great deal about the author's calculations. rather than attempt to redo the actuarial calculations performed to make the chart and assign this to the individuals in the table we should rather explain the concepts behind the 5% and 95% and preserve the intention of actuarial information as applying to demographic groups. 5% of people in the demographic the author selected live to _ age 95% of those people live to _ age and how this affects our subject population. [[User:Mrarch|Mrarch]] ([[User talk:Mrarch|talk]]) 21:43, 6 December 2013 (UTC)

Why is this explanation incomplete? The second paragraph does a good job explaining what the 5th percentile and 95th percentile are referring to. [[User:String userName = new String();|String userName = new String();]] ([[User talk:String userName = new String();|talk]]) 23:35, 19 June 2015 (UTC)

I prefer to think of the inhabitable planets as extensions to earth reserved for when we have learned not to kill all the inhabitants of the only inhabited planet in the universe. [[User:Weatherlawyer| I used Google News BEFORE it was clickbait]] ([[User talk:Weatherlawyer|talk]]) 22:39, 23 January 2015 (UTC)

I see no reason this is marked as incomplete; I've tidied up the percentile explanations, but haven't really added much more. I think it's fine, and will remove the incomplete tag in a few days if nobody objects. [[User:Cosmogoblin|Cosmogoblin]] ([[User talk:Cosmogoblin|talk]]) 13:53, 24 June 2015 (UTC)

'''UPDATED GRAPH:''' I've updated the image with a red line showing actual moon walker deaths. View here: [https://i.imgur.com/G7DbbBi.png]. Sadly, it's right on track. [[Special:Contributions/172.68.58.59|172.68.58.59]] 22:19, 9 August 2018 (UTC)

As of mid April, 2020, this prediction is still accurate, but I'm really scared of what it'll be by the end of 2020 or 2021. Stay healthy everyone, astronaut or not! [[User:PotatoGod|PotatoGod]] ([[User talk:PotatoGod|talk]]) 07:04, 22 April 2020 (UTC)

Interesting that 6/12 of all the people who walked on the moon were born in 1930, and all bar Alan Shepard was born 1930-1935. Reminds me of some of the ideas in Malcolm Gladwell's *Outliers* about there being especially good birth years to succeed at high levels in given fields. It seems you want to have been mid-30s to early-40s (Shephard the outlier at 47) in the late 60s/early 70s. This also makes the comic more dramatic - if there had been a wider spread of ages, then the "death curve" would be a lot more gradual. -[[User:Honeypuppy|Honeypuppy]] ([[User talk:Honeypuppy|talk]]) 01:15, 30 September 2020 (UTC)
What? No. That's a false correlation. The moon program took place over a very short span of time, and was looking for very specific qualification. Including age.

Honorary mention: Michael Collins (1930-2021), RIP this date. [[Special:Contributions/162.158.158.104|162.158.158.104]] 17:44, 28 April 2021 (UTC)
:Also Thomas Stafford (1930-2024). [[Special:Contributions/172.71.242.5|172.71.242.5]] 17:10, 19 March 2024 (UTC)
IMO the saddest part isn't astronauts dying - it's lack of any new people getting to walk on another planet. [[Special:Contributions/162.158.90.157|162.158.90.157]] 14:04, 5 October 2021 (UTC)
:Well, if the {{w|Artemis program|Artemis missions}} go as planned, the count might soon be increasing again for the first time in fifty-three years. Hopefully, not all of the remaining veteran astronauts will have died by then. --[[Special:Contributions/162.158.22.16|162.158.22.16]] 22:57, 4 August 2023 (UTC)
::But with increasing delays (now until 2026) the window of time is closing. [[Special:Contributions/172.71.242.43|172.71.242.43]] 17:03, 19 March 2024 (UTC)

Shouldn't we count also the people that traveled around the Moon?

Talk:3146: Fantastic Four

2025-09-30T15:49:31Z

140.141.134.242: a cruel reading...

And everyone wonders why that Franklin Richards kid is a little off... [[Special:Contributions/2601:8C3:8682:1FC0:9DB2:6777:1660:1D9C|2601:8C3:8682:1FC0:9DB2:6777:1660:1D9C]] 20:32, 24 September 2025 (UTC)

Could be worse. In Star Trek, the kid would be born 2 centuries in the past. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 21:06, 24 September 2025 (UTC)

Spoilers, Randall, spoilers...I'm sure there are other people who missed the theatrical release and are waiting for it to hit Disney+... [[Special:Contributions/128.4.149.3|128.4.149.3]] 21:22, 24 September 2025 (UTC)
:It's probably fine, the movie came out... two months ago.
:Holy shit it only came out two months ago. [[User:Redacted II|Redacted II]] ([[User talk:Redacted II|talk]]) 22:04, 24 September 2025 (UTC)
:This is how I learnt there was a new Fantastic Four movie [[Special:Contributions/64.114.211.124|64.114.211.124]] 23:25, 24 September 2025 (UTC)
:I had already heard of the movie, but only after it had been released. Whatever advertising they'd used had bypassed me... I only saw the 'poster' for it when someone who had already watched it included the image in a review. And, by my own (probably wrong) count, this is the fifth live-action FF film, anyway (one of them was made but never released, for... reasons) and I've only actually seen two of the prior ones. (Couldn't say for sure which plot-points belong to which. Was the one where Johnny Storm had a 'pre-powers-kicking-in' skiing accident different from the one with the dimensional travel thing? ...I think so, but then which order were they?).
:It seems that cinema releases are these days probably considered loss-leaders (and 'Oscars-qualifying') to justify subsequent online-platforming sales. I was lucky enough to have a fairly local cinema play The Thursday Murder Club, given that I don't have access to Netflix (or Disney+, or Paramount+, or all the rest that might be necessary to view all the various different franchises of possible interest) and am stubbornly unlikely to succumb anytime soon.
:As to spoilers, I'll have probably forgotten/disregarded this comic by the time I get to see this one. By which time there'll be an even newer re-re-reboot FF film, ''anyway'' (probably photorealistically generated with AI 'actors', and piped straight into subscribers' brains!), if not ''several'' more. [[Special:Contributions/82.132.244.45|82.132.244.45]] 02:06, 25 September 2025 (UTC)
::I think so but couldn't say for sure, I just know the one with the dimensional thing will always to me be "that movie where everyone forgets about Werner von Braun". [[Special:Contributions/128.4.149.3|128.4.149.3]] 13:11, 25 September 2025 (UTC)
::Man, I made a comment because I was mad about a spoiler for the sake of a horribly geeky pun and it set off whatever this is. [[Special:Contributions/128.4.149.3|128.4.149.3]] 13:11, 25 September 2025 (UTC)

Brings to mind the 1999 IgNobel Prize winner (in Managed Health Care), US Patent #3216423 ("Apparatus for facilitating the birth of a child by centrifugal force"), <https://patents.google.com/patent/US3216423A/en> {{unsigned ip|2601:189:8501:71a0:2ce2:fc8d:e6ee:d0f|00:21, 25 September 2025}}
:That's one crazy patent. Is that a net to catch the baby? Also this: "In the case of a woman who has a fully developed muscular system and has had ample physical exertion all through the pregnancy, as is common with all more '''primitive peoples''', nature provides all the necessary equipment and power to have a normal and quick delivery. This is not the case, however, with more '''civilized Women''' who often do not have the opportunity to develop the muscles needed in confinement." [[User:Mtcv|Mtcv]] ([[User talk:Mtcv|talk]]) 09:33, 25 September 2025 (UTC)

After I read the problem statement, I feared that they would somehow propel the baby out of her extremely fast to get momentum… o.O [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 07:32, 25 September 2025 (UTC)
:Actually, it needs to be slower.
:On ejecting the "baby mass" (presumably retrograde), the "mother mass" (and "mothership and the rest of its contents) gain a reactionary forward momentum. As soon as the baby is caught ''or'' skids to a halt on the deliver-table/deck (assuming artificial gravity, the capability of which might suggest a reactionless 'gravity drive' solution, anyway!) ''or'' hits the stern bulkhead, it applies rearward momentum to the ship.
:Due to the Oberth Effect, if you start this process (internal 'reaction thrust') at periapsis and manage to complete it (bring the bairn to 'rest', for internal ) at apoapsis then ''conceivably'' (...although that point was probably nine months earlier!) you could gain a maximal degree of assymetric momentum transfer in an orbital frame of reference.
:But the infant must have been 'free floating' (or on a friction-free surface effectively unaffected by the perpendicularly applied internal gravity field) for the whole duration. Including whatever rotational conditions apply. (If the ship as a whole is sent on a marginally higher orbit by the movement of the baby, than it would previously have been, then the baby must be on a marginally lower orbit up to ''its'' subsequent recorrection by the eventual 'ship catch'.)
:Though this may be impractical (without a huge ship-space to work within), you can{{Actual citation needed}} seemingly gain lesser effects by stretching the process out from periapsis 'birthing' to some pre-apoapsis 'catching'. The more instantaneous, though, the less effect, effectively to zero. (There's a slight change in the CoG of the mothership+baby system, but some thoughts on this might suggest 'forward birthing', or even 'upward', could redistribute the mass of the baby more out of the gravity-well for a marginal gain that is more than the marginal loss by combined the non-baby mass being sent fractionally deeper. But this very fine balance of effects seems to need more than the simple Newtonian calculations that normally suffice in orbital mechanics.)
:Also, if I interpret the scenario correctly, there ''is no'' apoapsis (when achieved), as the aim is to attain an escape velocity instead of a sub-escape one (by however marginal a difference). As in on, or over, the "parabolic orbit", towards being a useful hyperbolic one with a finite time to return to Earth, rather than just being an extremely eccentric elliptic one. So (apart from delaying the 'catch' by infinite time/distance) it's probably going to very much earlier than the original limit-of-apoapsis had nothing been done.
:But still as delayed as possibly, meaning that a ''veeerrryyy'' slow birth (and maybe also a stupendously long berth, as in habitation space!) is probablg what we need to be useful in a such a scenario. Or just somehow apply your internal control of gravity/inertia (as befits most sci-fi vessels, and is likely Reed Richards' department) to do something magical, propulsion-wise, or just whatever abilities Sue ('invisible forcefields', traditionally, not sure if they're in this film) and Johnny (the versions of him that happily 'flame-fly' through space, changing direction at will) could possibly bring to the party (distracted or not by a birth happening at the time). Heck, I bet Ben could just chuck something useless and massive out of the airlock (assuming they don't go full The Martian and throw their own air away) with his super-strength, and gain significant delta-V to make all the difference in any critically knife-edge situation as I'm imagining (not having seen this film, myself). [[Special:Contributions/82.132.246.64|82.132.246.64]] 11:30, 25 September 2025 (UTC)
::That is...not what the comic is saying though, nor is it what happened in the movie. It's merely connecting an event happening simultaneously with the boost with a pun on the Oberth effect. The writing in the comic could be a bit clearer that it's just two unrelated events happening concurrently. [[Special:Contributions/2001:569:FCEC:7F00:CDA6:30CD:A56D:5BF5|2001:569:FCEC:7F00:CDA6:30CD:A56D:5BF5]]
:::The comic is being deliberately humorous, of course, regardless of what might have happened in the film (like there was never actually an awkward conversation with Treebeard about why the Fellowship were all male).
:::The phrasing "and fire their engines at periapsis — as Sue has her baby — to get a boost" can be read numerous ways involving both coincidence and concurrence. Including the engines being fired to help the birthing process (c.f. the centripetal birthing device mentioned above)...
:::It all wouldn't look too out of place as a hook for a What-If question/answer situation, either, so of course various off the wall interpretions are going to be overanalysed for the purposes of humour. (Or overanalyzed for the purposes of humor.) [[Special:Contributions/82.132.244.95|82.132.244.95]] 07:11, 26 September 2025 (UTC)
Without watching the movie (and reading only a short comics, where no baby was involved) I had the impression that the baby was left around the neutron star, or even more cruel - sent into it.

Talk:3135: Sea Level

2025-08-31T17:55:07Z

140.141.134.242: Tidal range

Holy crud empty page! F1RST P0ST! [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 01:38, 30 August 2025 (UTC)
:2038: Last of the original Star Wars cast dies. <span class="nowrap">—megan [[user talk:megan|talk]] [[special:contribs/megan|contribs]]</span> 02:18, 30 August 2025 (UTC)
::What? If you're trying to get back at me because I was being useless and just "first posting", it's a reference to [[269: TCMP]], and I also, by the way, wrote the whole first paragraph of this explanation. [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 02:50, 30 August 2025 (UTC)
:::Alright, sorry, just realized what you did is a reference to [[493: Actuarial]]. Sorry about that! [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 02:53, 30 August 2025 (UTC)
::::I guess you're one of today's lucky [[Ten Thousand]]...
::::Wait, no, not everyone has read comic 493 by the time they're adults. I'm too lazy right now to calculate how many people learn about comic 493 each day, so I'll leave it as [[356|an exercise for the reader]]. <span class="nowrap">—megan [[user talk:megan|talk]] [[special:contribs/megan|contribs]]</span> 01:01, 31 August 2025 (UTC)

This one is related to the [https://xkcd.com/2809/ Moon] comic. [[User:Pgn674|Pgn674]] ([[User talk:Pgn674|talk]]) 01:39, 30 August 2025 (UTC)
:Clearly. [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 01:49, 30 August 2025 (UTC)

::it's almost a repeat. is he running out of ideas? [[user:lett‪herebedarklight|raeb]] 09:54, 30 August 2025 (UTC)
:::Hope not. [[User:RadiantRainwing|RadiantRainwing]] ([[User talk:RadiantRainwing|talk]]) 16:56, 30 August 2025 (UTC)
:::Why do people talk about running out of ideas? That is something I can't imagine. The world throws ideas and absurdities at you all the time. Running out of time to execute an idea - sure. Seems much more likely to be filtering error (have to check current idea against 3000 previous strips). [[Special:Contributions/107.77.205.64|107.77.205.64]] 19:42, 30 August 2025 (UTC)

Larry Niven had a story about alien-made indestructible spaceship hulls, except the makers didn't account for tidal effects when grazing a star. The test pilot was nearly ripped apart, but figured a way to survive. He sued their butts off against the guarantee. He concluded that their home planet did not have a large moon, a Clue. --[[User:PRR|PRR]] ([[User talk:PRR|talk]]) 02:41, 30 August 2025 (UTC)

I think I finally figured out the common thread. All the items here are here because they are elements of Life on Earth. The way the explanation was written kind of buried that important part of the comic.

Overall, if you just look at them as unrelated phenomena, then Lightning seems quite common. Islands made by microskeletons, and life-forms which change their form during development seem like they would be pretty common where there is life. Large tides - thought to be uncommon, but don't have much data, and models are hard. [[Special:Contributions/2600:387:4:803:0:0:0:A0|2600:387:4:803:0:0:0:A0]] 18:04, 30 August 2025 (UTC)

All planets with intelligent life we know have tides. In fact one could argue that tides play an important role in the development in life. Thus any intelligent observe is arguably familiar with tides. Thus the text is wrong in arguing that tides are surprising based on the observation that most known planets likely do not have large tides. --[[Special:Contributions/2A01:599:114:9E35:D827:C56:FF88:1858|2A01:599:114:9E35:D827:C56:FF88:1858]] 19:09, 30 August 2025 (UTC)

:Argument has problems - insufficient sample size, selection bias. Nothing in the comic talked about intelligent life.
:The role of tides in development of life certainly makes sense to add.
:Tides are strange in that they are very complex and hard to explain in detail. Fluid dynamics in a very complex, non-ridgid vessel, involve gravitational forces from multiple bodies. [[Special:Contributions/107.77.205.64|107.77.205.64]] 20:00, 30 August 2025 (UTC)

:: Sample size is definitely a problem. Nothing in the comic talks about tides being strange in a cosmic sense. They are just very weird for one of the two observers from earth. --[[Special:Contributions/195.63.76.62|195.63.76.62]] 20:39, 30 August 2025 (UTC)

I'm shocked that Randal didn't include some sort of reference to climate change- and how tides effectively, at least in 2025 and for the foreseeable future, dwarf sea rise due to melting ice. [[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 20:18, 30 August 2025 (UTC)
:On a (twice-)daily basis, yes. But that's like saying an unseasonal/hyperseasonal cold snap belies the possibility of global warming. (If that's the point you're trying to make.)
:And I'm not sure if you're saying that Randall "is the sort of person who would go on and on about climate change, but for soe reason he surprisingly didn't do so here" or "he really ought to be mentioning climate change at every opportunity, but he missed the opportunity to convey the concept"..? I'd disagree with ''both'' of those assessments of his (non-)inclusion here, though, and perhaps you're even coming from a completely different third direction that I might or might not understand. But really not the place to discuss it, as he obviously hasn't made that part of the joke/message in this comic. [[Special:Contributions/92.17.62.87|92.17.62.87]] 23:27, 30 August 2025 (UTC)

Lightning should be common throughout the universe, as the ingredients for it (planetary atmospheres containing things like dust that can build up differential static charges through agitation) appear to be. It's still a very weird phenomenon, with many aspects not understood (how does the triboelectric effect work, can breakdown patterns be predicted, wtf is going on with sprites and ball lightning, etc) but it really isn't likely to be rare. --[[Special:Contributions/81.96.108.67|81.96.108.67]] 05:48, 31 August 2025 (UTC)

Ten feet tidal range on a remote island - isn't this too much? I thought it should be less, with stronger tides only in some gulfs where an amplification exists. https://en.wikipedia.org/wiki/Tide figure 15 shows 5 feet tidal range maximum