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3058: Tall Structures
| Tall Structures |
 Title text: Briefly set a new record for tallest human-made structure by getting my knit sweater snagged on the skydiving plane door as I jumped and not noticing until I'd landed. |
Explanation
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This explanation is incomplete: Created by the OSTANKINO TOWER - Please change this comment when editing this page. Do NOT delete this tag too soon. If you can fix this issue, edit the page! |
This is a comparison of various tall buildings and other structures, ranging from the largest pyramid of Giza to the Burj Khalifa, sorted by increasing height. It mimics common illustrations of successive tallest buildings/structures in the world through time, or the current 'top few' examples, but instead represents an idiosyncratic selection. The pyramid of Giza was the tallest structure in the ancient world, and the Burj Khalifa is broadly acknowledged as the tallest building in the world.
When comparing the tallest structures of various types, the question of definitions often becomes important. Some define the heights of buildings to their highest occupied floor, while others (including all permanent structures) may include merely-aesthetic spires or have arbitrary installations of antennae on top of the building (which may comprise a significant portion of the building's height). Potentially all of an uninhabited and sealed pyramid could be considered structure alone, with any of its internal voids left unusable, practically inaccessible and definitely beyond sight.
There's also the question of whether structures need to be self-supporting to be counted, since structures such as antennae may be extremely tall but only stay up with the help of guy-wires. In this comic, Randall seems to take the broadest possible definition, apparently defining a "structure" as any artificial construct with continuous extent from the ground to its height. The comic then demonstrates how ludicrous such a broad definition becomes, by portraying a "random aerostat", tethered to the ground by a long cable, which is by far the tallest structure on the chart, significantly exceeding the height of the Burj Khalifa.
An aerostat is a lighter-than-air aircraft that can be tethered to the ground. A kite balloon (or kytoon) is a variant of the aerostat where the balloon body includes a lifting-body or kite design for additional lift. It is more stable than a balloon in winds and tends to hold its position above the tether. This is the main joke of the comic, since as long as it is tethered to the ground and is higher than the Burj Khalifa, it could be considered the tallest man-made structure. Since aerostats (and similar tethered flying objects) are generally not counted as "structures", this points out that, without agreed-upon and restrictive definitions, the question of what's tallest quickly becomes meaningless. There is a class of structures, typically seen in oil platforms, that are "medium supported" and that use buoyancy to stand 'tall' above their anchored deep-sea end in an otherwise freestanding manner; there are clear parallels to the concept of a tethered balloon, and one such structure had indeed been touted by some as the "tallest free-standing structure" up until the Burj Khalifa physically surpassed it.
The comic doesn't accurately depict the world record for how high tethered aerostats can actually fly (4880 meters, achieved on 23 September 2014, close to 6 times the height of Burj Khalifa), which would either dwarf the other buildings or make the comic very tall, but since it is just some random aerostat flying at that time that is shown, this may be at a much lower height.
The title text takes this point even further, claiming that Randall once skydived out of an airplane wearing a knit sweater, which caught on the airplane door, and presumably unraveled as he descended. The implication being that the yarn unraveled without breaking during his entire descent. When he reached the ground, the long thread presumably extended from his body up to the plane (typically 2,400–4,300 m, or 8,000–14,000 feet, above the ground). For the tiny moment between when he hit the ground and when the thread snapped or came loose (since the plane would still be moving), this would "briefly" form a structure, under the broadest possible definition, and would therefore set a new record. This is obviously not realistically feasible. Even if a thread could remain intact and connected under such circumstances, most knit tops don't have nearly enough thread to reach that kind of height.
Table of structures in the comic
| Name | Height | Tallest structure | Explanation |
|---|---|---|---|
| The Great Pyramid (Giza) | 137 m (449.5 ft) | c. 2570 BCE–1311 CE | A famous pyramid built c. 2570 BC |
| The Shard (London) | 309.6 m (1,016 ft) | – | A skyscraper with steeply angled sides, the tallest 'habitable freestanding structure' in the UK. |
| The Eiffel Tower (Paris) | 330 m (1,083 ft) | 1889–1930 | A wrought-iron lattice tower named after its designer, Gustave Eiffel |
| The Empire State Building (New York) | 443.2 m (1,454 ft) | 1931–1967 | An art-deco office tower often seen in media |
| The CN Tower (Toronto) | 553.3 m (1,815 ft) | 1975–2007 | A communication and observation tower in Canada |
| The Clock Towers (Mecca) | 601 m (1,972 ft) | – | A hotel complex featuring the largest clock in the world |
| KRDK-TV mast (North Dakota) | 630 m (2,060 ft) | – | Current tallest structure in the United States (KVLY-TV mast was previously taller) |
| Shanghai Tower (Shanghai) | 632 m (2,073 ft) | – | Tallest skyscraper in China |
| Tokyo Skytree (Tokyo) | 634.0 m (2,080 ft) | – | Tallest tower in the world |
| Merdeka 118 (Kuala Lumpur) | 678.9 m (2,227 ft) | – | A skyscraper with diamond-shaped facades |
| Burj Khalifa (Dubai) | 828 m (2,717 ft) | 2007–present | Tallest structure in the world |
| Some random aerostat that happens to be operating today | ~1,280 m (4,200 ft) (Depicted) ~4,600 m (15,000 ft) (Actual) |
Varies | The main joke in the comic |
Transcript
- [Labels below structures shown in a black silhouette, from left to right, shortest to tallest:]
- The Great Pyramid (Giza)
- The Shard (London)
- The Eiffel Tower (Paris)
- The Empire State Building (New York)
- The CN Tower (Toronto)
- The Clock Towers (Mecca)
- KRDK-TV Mast (North Dakota)
- Shanghai Tower
- Tokyo Skytree
- Merdeka 118 (Kuala Lumpur)
- Burj Khalifa (Dubai)
- Some random aerostat that happens to be operating today
- [Caption below the panel:]
- The Burj Khalifa is the world's tallest artificial structure, but only on days when no one is flying a high-altitude kite balloon aerostat.
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- This is not actually possible, since a knit garment is not made from one long thread of yarn, but many interwoven threads.
This is actually wrong; knitting is a technique for entangling a single yarn with itself in such a way that it forms a fabric. (It's not to be confused with weaving, which does indeed use many, shorter threads.) In practice, a large, complex item like a sweater is made from multiple pieces sewn together, but it would have something like a single digit number of separate yarns.
Incidentally, a sweater contains on the order of a kilometer of yarn, which is also about the minimum safe distance for skydiving, so this scenario passes the Fermi estimate sniff test. 162.158.159.100 00:55, 4 March 2025 (UTC)
- Wouldn't the yarn snap at some point from acceleration due to gravity and the tightness of the weave pattern? TomtheBuilder (talk) 01:56, 4 March 2025 (UTC)
- Usually, the plane you are skydiving from won't remain circling above you ... -- Hkmaly (talk) 03:22, 4 March 2025 (UTC)
- 1000m is the height where you should start considering opening your chute, so you wouldn't do much skydiving if you jumped from that height. Beginners will start aroung 1500m to have a few seconds of free fall before opening, advanced skydivers somewhere between 3000m and 5000m.172.68.151.30 11:59, 5 March 2025 (UTC)
- Reminds me of the old (often retold, often varying, probably more apocryphal than not) about the Gurkhas, the British 'overseas' branch of the army which is rightfully honoured and feared for its bravery and tenacity and basically being a compact bundle of badass.
- At some point (typically in WW2), the idea arises that it would be useful to drop a regiment or two of them behind enemy lines. They are approached with the idea of undergoing training, which they readily volunteer for, and then they get the full briefing.
- British Officer: We'll take you up in the plane and drop you from <given height>, on your first training flight.
- Gurkha Officer: That sounds rather high, can we perhaps try <slightly lower height> for our first attempt?
- British Officer: I wouldn't advise that, you need a bit more height just to make sure your parachutes open properly.
- Gurkha Officer: Oh, we'll have parachutes? Ok then, no problem!
- ... 172.70.160.252 13:52, 5 March 2025 (UTC)
This is kinda random, but does this wiki have a page for xkcd.com/no and xkcd.com/yes?? I didn't see any and I think they at least deserve a page 172.69.23.94 (talk) 04:32, 4 March 2025 (please sign your comments with ~~~~)
- Huh that's cool, didn't know those pages existed. Do you know anything about why they exist? (also please sign your posts with ~~~~) TheTrainsKid (talk) 05:50, 4 March 2025 (UTC)
- Weird. Here with active links: yes and no. Not sure where to put this, maybe under the explanation of xckd or the structure of the page? Hmmm --Kynde (talk) 09:30, 4 March 2025 (UTC)
- Still no idea why they exist? I was hoping somebody had already sleuthed it out. 162.158.167.65 15:04, 4 March 2025 (UTC)
- I'm about 80% sure it's for What If. 172.71.10.242 13:43, 5 March 2025 (UTC)
- Still no idea why they exist? I was hoping somebody had already sleuthed it out. 162.158.167.65 15:04, 4 March 2025 (UTC)
- Weird. Here with active links: yes and no. Not sure where to put this, maybe under the explanation of xckd or the structure of the page? Hmmm --Kynde (talk) 09:30, 4 March 2025 (UTC)
Nice to see the UK officially represented, there, but it's not even the tallest tower in the UK (and that's not counting the seven or eight latticework masts that range from merely taller than The Shard to even taller than EMTS). I suspect similar absences feature in the rest of the list, which I note yet features other freestanding towers-but-not-buildings (plus the 'joker' neither-tower-nor-building that is the aerostat). 172.70.163.142 07:06, 4 March 2025 (UTC)
Should we delete the mention of a tall structure left out or make a list? Moved it to a trivia section and removed the personal "On the woeful lack of Ostankino TV tower" section heading. But I feel it should be left out and the one making that change should have posted it in this discussion page in stead. --Kynde (talk) 09:30, 4 March 2025 (UTC)
- I'm sure there's a definitive list of "tallest artificial structures (not shown in the comic)", which we can decide the full criteria for (a number of additional broadcasting masts, self-supporting alone or guy-roped, plus maybe various oil-platforms that are sufficiently tall if you measure from the subsurface base). The (now-Triviaed) Ostankino intormation should not really sit there alone, without various other absences noted (see just above your comment, in this Talk/Discussion section).
- If we were to add other examples, though, we could do without a lot of the extra information, just keep it no more complicated than the table with the comic-depicted structures. (One option is, indeed, to open up the comic's table to off-comic examples, those lines being given a light grey cell background to distinguish any which aren't on the comic, and distinguish masts, towers, buildings, rigs(?) and (the lone example of) tethered aerostat.) 172.70.160.253 12:20, 4 March 2025 (UTC)
- Postscript: became confused as to why the table I'd originally seen here no longer was. It got removed, but I don't understand why. Anyway, if it really doesn't belong in the Explanation, put it into the Trivia section instead and then add any desired relevent Otsankino/etc lines in as well...? 141.101.98.178 12:35, 4 March 2025 (UTC)
Comment thread for the inclusion of the table, if you have an opinion, state your opinion first with "KEEP" or "REMOVE" and then explain your position below. TomtheBuilder (talk) 12:38, 4 March 2025 (UTC)
- As the above IP (in double-reply to Kynde), KEEP because we have (or should have) plenty of similar tables-of-things-in-the-comic, and this is exactly in line with that. If there's any serious reason why it is superfluous in the Explanation, it'll go in the Trivia, but I can't currently see why it needs to be moved. But I look forward to the (twice-?!)removing IP, or any other individual, justifying the "we don't need" attitude. (Also, as I can't provably change my vote, even if ever persuaded otherwise, don't try to count this or any other IPs in the tally. This is an indicative statement only.) 141.101.98.248 12:53, 4 March 2025 (UTC)
You could add a Wikipedia link to https://en.wikipedia.org/wiki/Ostankino_Tower. --162.158.175.72 13:45, 4 March 2025 (UTC)
- At the time of this suggestion, there actually was such a link. Though it was removed in a later (justified, IMO) removal of the disproportionately off-comic focus on this particular structure (amongst manner others that exist and were neither in the comic nor given 'explanation space'). But you've mentioned it here, too, so fear not! 172.70.162.196 17:26, 5 March 2025 (UTC)
I'm interested to know what sort of garment would Felix Baumgartner need to wear to qualify for the highest structure award when jumping from 36,402.6 metres. --Alos (talk) 14:10, 5 March 2025 (UTC)
- Long Johns? (Though perhaps more like what Kittinger would wear, than Baumgartner or Alan Eustace...) 172.70.162.196 17:26, 5 March 2025 (UTC)
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