Talk:2087: Rocket Launch

2023-11-06T18:00:50Z

172.71.26.192: Added comment

I had to fight the urge to type Care Bare [[User:Arachrah|Arachrah]] ([[User talk:Arachrah|talk]])

This was published during the Arianespace launch livestream, between launch and satellite deployment: https://www.youtube.com/watch?v=mpHJoo0h8GQ [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 17:11, 19 December 2018 (UTC)

Looks like it could be an Ariane5 in the comic, it is a 3 stage. Anyone know if Max-CB is a real thing (and before I get any wisecracks, I know there aren't any Care Bears in the clouds) [[Special:Contributions/162.158.63.214|162.158.63.214]] 20:27, 19 December 2018 (UTC)

: A search for rocketry terminology reveals that Cb stands for Ballistic Coefficient, which is a measure of the ability to coast. It is related to both velocity and air density, which vary throughout a rocket launch, so it makes sense that there might be some point of maximum ballistic coefficient. (Note: I am not a rocket scientist, and this is clearly rocket science, so take this with a grain of salt!) [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 21:13, 19 December 2018 (UTC)
::That point is called "Max-Q". Source: I've seen a lot of rocket launches recently and they always mention it, because it's the second most likely moment to have a failure (first is the launch, of course). [[User:Fabian42|Fabian42]] ([[User talk:Fabian42|talk]]) 07:28, 20 December 2018 (UTC)

: Pontificating further, it is reasonable to conjecture that as a rocket accelerates to higher speeds, the drag from the atmosphere increases with increasing speed, but past a certain point the drag begins to decrease as the air gets thinner. This suggests there is some point somewhere during the launch sequence where aerodynamic drag reaches a maximum value - aka Max Cb. [[User:Ianrbibtitlht|Ianrbibtitlht]] ([[User talk:Ianrbibtitlht|talk]]) 21:26, 19 December 2018 (UTC)

: Finally one I can help with! Okay, I don't think this is ballistic coefficient for several reasons: 1. Ballistic Coefficient is typically noted by the greek letter Beta, not Cb. 2. Ballistic coefficient is mass divided by drag area (drag coefficient times reference area). Basically a shape parameter. So while the mass does change over the course of the flight (burning fuel), the drag area does not. Making this a somewhat useless parameter for a launch vehicle 3. Ballistic Coefficient is typically reported as a static parameter rather than a time-varying parameter, so "Max ballistic coefficient" is a rather unusual metric (and would occur on the launch pad in any case, when mass is highest). Finally, as an aside, objects with high ballistic coefficients tend to fly through the air easily and are not influenced very much by wind (such as rocks or bullets), whereas low-beta objects can by pushed and slowed down a lot by the wind (such as balloons). [[User:Tyanderson91|Tyanderson91]] ([[User talk:Tyanderson91|talk]]) 03:17, 20 December 2018 (UTC)
:: For rockets with side boosters, as the one shown, drag will potentially change dramatically at each staging event; when the side boosters are jettisoned they are no longer dragging on the rocket, and it's possible that the stage will have a higher ballistic coefficient because there's less surface area and not significantly less mass. Chad[[Special:Contributions/172.68.47.84|172.68.47.84]] 10:30, 20 December 2018 (UTC)

r/shittyspacexideas --[[Special:Contributions/173.245.52.139|173.245.52.139]] 19:53, 19 December 2018 (UTC)

If you trace the dotted lines, it seems that the Boosters are the winners[[User:CCCVVVA|CCCVVVA]] ([[User talk:CCCVVVA|talk]]) 03:02, 20 December 2018 (UTC)

:When I did it, I noticed that the boosters lost. After reading your comment, I traced it again and noticed that the last time they meet, when I saw them not crossing, could actually be interpreted as crossing (though it still seems to me that not crossing is more likely). Wonder if thst's purposeful confusion. [[Special:Contributions/162.158.89.223|162.158.89.223]] 01:26, 21 December 2018 (UTC)

This was posted on the day SpaceX was supposed to launch the GPS-III-2 satellite, which may be the reason for the mention of GPS [[User:Tyanderson91|Tyanderson91]] ([[User talk:Tyanderson91|talk]])

The max CB is clearly meant to spoof the real problem of rockets hitting birds. Since birds can't fly in the he upper part of the atmosphere, the point of highest likelihood of hitting a bird would presumably be below max-Q and not above it as in the comic. It is worth noting that there are no clouds at the altitude where max CB is shown in the comic, so it seems unlikely that any hypothetical cloud castle would be that high.

EDIT: ok, after checking the numbers it seems like it is technically possible to encounter birds and clouds at heights above max-Q for some rockets, but the position shown in the comic still seems too high. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 04:23, 20 December 2018 (UTC)

I suspect "pursuit phase" refers either to [https://en.wikipedia.org/wiki/Pursuit_predation predation] or to some aspect of air warfare (either involving missiles chasing craft or craft vs. craft). [[User:Magic9mushroom|Magic9mushroom]] ([[User talk:Magic9mushroom|talk]]) 08:08, 20 December 2018 (UTC)

I believe "pursuit phase" refers to the Domestic Violence Cycle. There are just too many correlations. [[User:iraytrace|iraytrace]] ([[User talk:iraytrace|talk]]) (02:38 21 December 2018 (UTC)
:I see no reason what so ever that Randall was thinking of domestic violence, just because he called a pursuit of one rocket of another a "pursuit phase". Guess someone has this on their mind and see it everywhere. I would delete it but I don't have the time. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 14:01, 21 December 2018 (UTC)

::Pursuit phase or [https://en.wikipedia.org/wiki/Pursuit_guidance pursuit guidance] is something that crops up in missile guidance and ICBM interception a lot, which I think is probably more relevant here. --[[Special:Contributions/108.162.246.203|108.162.246.203]] 18:24, 21 December 2018 (UTC)

I feel a reference to [[1133: Up Goer Five]] and 'will not go to space today' is needed, but not sure where - after dogfight? Possibly Kerbal (Care Bear?) Space Program too. [[Special:Contributions/162.158.34.178|162.158.34.178]] 15:09, 21 December 2018 (UTC)

I think there's some kind of a theme going on with the reunified stages & a traditional narrative arc of rise, fall & redemption (or something like that..). Like it's rising from its fall to try to regain a throne or something? I'm not sure where to put it but edit it in if you agree.
Also not changing it, but linking Wikipedia's article on 'pursuit guidance' as a 'possible reference' is a helluva stretch, don't you think? Cool article, but I don't think it's referenced any more than 'CB Radio' or 'Q-tips' would be
¯\_(ツ)_/¯ --[[Special:Contributions/172.69.22.224|172.69.22.224]] 18:46, 24 December 2018 (UTC)

The GPS disabled may also be a reference to the COCOM altitude/speed limits placed on commercial GPS units. [[Special:Contributions/162.158.63.232|162.158.63.232]] 16:22, 25 December 2018 (UTC)

This comic can be solved by simply deleting a white space and replacing "a typical" with "atypical" [[Special:Contributions/162.158.91.125|162.158.91.125]] 10:04, 4 January 2019 (UTC)

Could the 'pilot panics' stage be a reference to JetBlue Flight 191, an incident where the pilot had an apparent mental breakdown and was locked out of the cockpit and restrained by passengers? https://en.m.wikipedia.org/wiki/JetBlue_Flight_191 [[Special:Contributions/141.101.98.238|141.101.98.238]] 12:05, 2 November 2023 (UTC)
:If it had been less than six years prior, perhaps, and no other comparable incidents (like the Germanwings Flight 9525 one, that didn't turn out so well) betweentime. I think it's just a trope, at this point. [[Special:Contributions/172.70.90.7|172.70.90.7]] 13:47, 2 November 2023 (UTC)

The "Inter-stage dogfight" appears to be a rolling scissors dogfight. The two craft would have engaged at fairly high speed and are doing a "scissor" movement to try to get on the other craft's tail and destroy it. https://en.wikipedia.org/wiki/Scissors_(aeronautics)#:~:text=Whereas%20the%20flat%20scissors%20typically,attack%20at%20a%20higher%20speed.

2820: Inspiration

2023-08-28T13:52:10Z

172.71.26.192: Link for biographer

{{comic
| number = 2820
| date = August 25, 2023
| title = Inspiration
| image = inspiration_2x.png
| imagesize = 515x163px
| noexpand = true
| titletext = An apple fell on Isaac Newton's head and gave him the idea that the moon might be a tasty apple, though this turned out not to be true--the Apollo program eventually determined that it was just a desolate and bland Red Delicious.
}}

==Explanation==
{{incomplete|Created by a HELIOCENTRIC RED DELICIOUS APPLE - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

The apple falling on Cueball's head is a reference to the folk tale about the inspiration for {{W|Newton's Law of Universal Gravitation}}. [https://www.newtonproject.ox.ac.uk/view/texts/normalized/OTHE00001 One of Isaac Newton's biographers] reported that his inquiries into the nature of gravity were "occasion’d by the fall of an apple" as he sat under a tree. Over time, this evolved into the story that a falling apple struck Newton on the head. Some versions of the story imagine him gazing at the moon when the apple hits him, and having the revelation that the force pulling the apple toward the earth was the same force that kept the moon in orbit.

In this strip, Cueball is similarly struck by a falling apple, while gazing at the moon. But rather than an insight about gravity, he makes a different connection, that of starting an apple orchard on the Moon. This would, of course, require some form of massive terraforming project (or at least the construction of a large, pressurized dome), since the airless environment of the moon wouldn't allow any plants to survive. It's not entirely ridiculous that the contrast between the lifeless moon and the lush landscape of an apple orchard would inspire someone to seek to plant life on the moon.

The title text claims that Newton thought that the Moon was in fact a tasty apple, but the {{w|Apollo program}} proved it was a {{w|Red Delicious}} apple. This is a jab at Randall's least favorite type of apple, as has been [[388|previously]] [[1766|noted]]. That apple variety became the most popular variety in the USA after its introduction but, to satisfy market demand, growers began selecting for storage and cosmetic appeal over flavor and palatability. Popularity has declined significantly in recent decades. "Desolate and bland" echoes Apollo astronaut {{w|Buzz Aldrin}} describing the moonscape as "magnificent desolation".

The tale of Newton and the apple was previously mentioned in [[1584|1584: Moments of Inspiration]]

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Cueball sits under a tree. An apple falls from the tree and hits him on the head.]
:Bonk

:[The view zooms out, showing the moon, which Cueball looks up at.]

:[Closeup on Cueball.]
:Cueball: ...

:Cueball: ''We should grow apples on the moon.''

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring real people]]
[[Category:Astronomy]]
[[Category:Physics]]
[[Category:Food]]

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Talk:2087: Rocket Launch

2820: Inspiration