513 is 33 × 19, which makes it a Harshad number in base-10 (numbers divisible by the sum of their digits; 5+1+3=9).
- You know the super-robot anime trope of the person that stands in the giant robot's hand? Well, I did some computing of the minimum size for a palm to support a person. Minimum standing area for a person is .6 meters, or 6.46 square feet, or a square 77.46 centimeters or 30.5 inches on a side. The area of the human palm is .5% of the surface area of the body, and the average surface area of a male human body is 1.9 square meters, or 20.45 square feet. .05% of that is 95 square centimeters (.0095 square meters), or 14.73 square inches (which is also .1023 square feet). Dividing 20.45 by .1023 (the area ratio of "standing space" to "palm area"), we get 24.85—so a figure with palms large enough to stand on must have 24.85 times the area of a human body. Area varies as the square of single dimensions, so the minimum size for a giant robot to have someone stand on its palms (the square root of 24.85=)4.985 times the height of an average human male. The average human male (globally) is 68 inches or 172.7 centimeters tall, and 4.985 times that is 28 feet, 3 inches, or 8.61 meters. Assuming the approximate density of automotive magnesium alloy, which again makes an average man mass 119 kilograms instead of 70, the robot will mass 14,746.18 kg, or 16 short tons, 509.8 lbs.
- I know I've mentioned that the "thieves' guilds" and "mages' guilds" in a lot of fantasy RPGs, aren't really guilds. The mages' ones at least do have apprenticeships, which most thieves don't, but prospective members don't need to submit a masterwork to get in and they very rarely offer insurance.
It's worse in computer RPGs, where the "guild" is the thing through which professionals are hired (guilds didn't do that—again, you don't contact the ADA when you're looking for a dentist) and they seldom even organize around a particular craft. That's no kind of a guild. (They're also not anything like an "order"—the "Order of the Stick" is not a vowed lay or monastic brotherhood, military or otherwise, therefore it should be called something else.) No, what the adventurer-group in a computer RPG is, and what many little bands of adventurers in the tabletop games often are, is basically similar to the mercenary companies of the late Medieval period and after, albeit with more sua sponte work and in more fields than the purely military.
I personally hate the convention of actually referring to the adventurers, in-world, as "adventurers". "Adventurer" is a word with very bad connotations—it's something along the lines of "bounder". Plus, nobody actually doing the things would regard them as "adventures". "Explorer" is probably closer, given what they do (and their dungeon-delvings, thus, are "explorations"); if one wanted to highlight the similarities to mercenary companies, I suggest something like "contractors", or some synonym (the actual literal meaning of "condottiero" is "one who conducts [war]", much like calling a mortician an "undertaker [of embalming]"). - Of course, I realize as I write that, the underlying objection is that I don't like RPGs that feel like games ("I don't want dreams where it feels like I'm dreaming"). So, for instance, I dislike most recent fantasy anime and manga, since the characters all but talk about literally leveling up and having hit points. Fairy Tail, and the many series that are obviously knockoffs of Fairy Tail, would be the prime offender there (meanwhile, Lodoss War doesn't do it, despite having originally been an actual transcribed D&D campaign).
This, along with their PC bullshit and chronological blackface minstrelsy, is why I can't get behind Pathfinder (well, that, and I prefer 3.0E to 3.5E...and also their new classes fix what wasn't broken, if your DM is remotely competent). The "Pathfinder Society" of the core setting is a loathsome anachronism on par with light novels inserting the godforsaken Japanese school system into everything, even post-apocalyptic anarchies and trans-human societies that live on Dyson spheres. (It's also a transparent knockoff of the Traveller's Aid Society, except that that has a right to exist, in a science fiction setting.) - Might give the khângây handheld coilguns, after all, instead of electrothermal-chemical. Coilguns (or Gauss guns) don't have the issues railguns do, namely needing a hugely long barrel. A quick survey of the web with my peerless Google-fu reveals an approximate equivalency between total muzzle energy and the power requirements of the coilgun, so it doesn't need weird little slivers at hyper-velocity, it can just use regular bullets and normal muzzle energies. Actually think I'll call theirs "quench guns", which is the term for superconducting coilguns (even though the khângây model probably uses "hot" superconductors, they're usually still pretty cold—"hot" is relative to "below 30 Kelvin", which is what metal superconductors need).
Still torn as to whether I ought to call the ones the humans use—that rotate between barrels to save wear on the components?—"coil vulcans" or "Gauss vulcans". The former seems more technical; the latter has more of a science-fictional pedigree. Then again, avoiding the science-fictional term and saying something else (not "holograms", "volumetric displays"; not "cyborg limbs", "prosthetic enhancements") is how I roll—because you want people to look at the thing, not their memory of tropes about the thing—so I guess "coil vulcans" it is. Then again "vulcan" is itself a science-fictional term, for what would probably be more correctly called a "Gatling autocannon" or "minigun" (depending on caliber)—but it's primarily used in Japanese science fiction, so my English-language audience wouldn't have too many tropes associated with it. - In light of the extreme energies possible by putting explosives in one's rounds, I'm upgrading zled high-end powered armor (as used by their regular military rather than civilian emergency levies) to STANAG 4569 Level 4—it had been 3, I compared it to a Russian VPK-3927 Volk (pronounced as it's spelled, not with an F—it's the Slavic word for "wolf"), which is basically a hardened Humvee. But now I'm upgrading their armor to the level of a Matador MRAP. Of course, since the armor is "adaptive" rather than using static mechanical qualities (otherwise it would be either really dense or too bulky to move in), a whole lot of energy packed into half a millisecond and a circle the same diameter as a pin's head—a laser—can punch through too fast for the structure to "adapt". I think several of the humans' armor-piercing explosive rounds, in rapid succession, can also dish out more energy than the armor can cope with, but for one-hit kills humans still need anti-tank grenades.
- Speaking of STANAG 4569, I can't believe I've neglected to mention (although I've made oblique references) that a major form of "K-Mart Realism" in my SF is that things are referred to by their ISO designation, if they have one. Prolog, the computer language, is ISO 13211; Unicode, the character-encoding standard, is ISO 10646. There doesn't seem to be an ISO standard for vehicle armor, but personal armor is ISO 14876; I imagine that the ISO of the 24th century will have a vehicle-armor standard, but I'm not gonna say what its number is. Those numbers aren't random, but their system is crazy hard to figure out. It's entirely likely it'd incorporate a (technologically updated) version of STANAG 4569, a lot of ISO standards are just various American or European standards given a new name.
This is a thing I prefer to do: when there's already a real thing for it, go with the real thing. The UN's space agency in my books is the Office for Outer Space Affairs, because that's what the UN's space agency is called. The UN's military are the Peacekeepers, because that's what the UN's military is called (it doesn't quite work the same way as now, of course—national armies are more like the "national cadres" in the Soviet Army). The UN's court is the International Court of Justice, and its police are the UNPOL (yeah, they just call 'em "UN Police"—look at it this way, they didn't waste time coming up with a name on the world's taxpayers' dime). - Decided to change most of the Chinese in my books to Mandarin, although I still like the sound of Cantonese better. I discovered something while I was doing it: Mandarin has no lateral/post-alveolar consonants (the "sh" in English). It has palatal ones (the "sh" from Japanese), and retroflex ones (the "sz" in Polish, or like the ř in Dvořák—actually the "r" in many dialects of English, including the main American and Canadian ones, is a retroflex approximant, which is weird for a Western European language), but no laterals. Cantonese has them, including the approximant (the "ll" in Welsh) in the Taishan dialect, but no retroflex ones. (Is my preference for Cantonese's sounds in part because I can pronounce them? Your guess is as good as mine.)
I took another look at Mandarin's sounds because I was thinking "it has no phonemic voicing—b, d, and g are actually pronounced as p, t, and k, which in turn are used to write the aspirated versions of themselves—so what are j, z, and zh?" The answer is "the 'ch' in Japanese, 'ts', and 'the unvoiced retroflex affricate' (basically t + the sound of Polish 'sz')", respectively. C, in case you wondered, is "aspirated 'ts'", sh is "the sound of Polish 'sz'", ch is "aspirated unvoiced retroflex affricate", q is "aspirated 'ch' from Japanese", and x is "the 'sh' from Japanese". Pinyin Romanization felt itself free to use unorthodox interpretations of the Roman alphabet, repurposing redundant letters much as the ancient Greeks turned Phoenician consonants Greek didn't have into the first vowels in any alphabet, ever. - Turns out, I was wrong. Cats adapt fast to free-fall conditions. I don't know why I didn't search "cats zero-g" before. But apparently, after a brief time when they have no idea what to do, they, like mice and squirrels, just behave normally. Maybe having a much more finely-tuned balance system means they can learn to adapt to free-fall more quickly.
This means zled ships can use rotation gravity—which is good, because realistically you probably can't have topology artificial-gravity inside the metric-patching field. The minimum diameter to produce 1.08 Gs (1 G if you're a zled) is 241.449997 meters (yes, I calculated it to the micron), which means the smallest zled ship would be, essentially, a Bernal sphere. The O'Neill Island One has, after all, a radius of 250 m. If we want all of it to have basically the same gravity, limiting ourselves to a rotating band 20 degrees wide, centered on a great circle of the sphere, seems reasonable. On the minimum-diameter sphere, it has a surface-area of 114,650 square meters—which is 28.3 acres, or a bit over a quarter the area of Vatican City.
The real trouble with rotation gravity is figuring out how to synch up non-spinning things that dock with the ship with the spin of the spinning part. My calculations say I can probably do it with an elevator as long as the radius of the ship, accelerating all along its length at almost exactly half a zled gravity, but I wonder if I'm not missing something. The rotation even of the big one (909 m in diameter) is still 69.3808 meters per second, which is 249.771 kilometers per hour (or 155.2 miles). Then again the Earth's surface is moving a lot faster than that (depending on your latitude—at the equator, 1/1440 rpm translates to a tangential velocity of 463.8 m/s, 1,669.76 kph, or 1037.54 mph), so maybe it's not a problem? Maybe it can be compared to aerial refueling, and that routinely happens at 315 knots (which is 583.38 kph or 362.5 mph). - Speaking of the speed the Earth rotates, the tangential velocity varies by latitude. The circumference of a circle that passes through, say, 28°31′26.61″N, 80°39′3.06″W, is approximately 35,237.49 kilometers (the circle of the equator is 40,075), meaning that its tangential velocity is 407.84 m/s, 1,468.23 kph, or 912.32 mph. That's why space-launches are always toward the east—it takes 408 m/s off the speed the rocket has to accelerate to by its own power. Escape velocity for the Earth is 11,200 m/s, so launching eastward grants a 3.6% savings. That's nothing to sneeze at in rocketry.
2 comments:
So tangential velocity is greater at lower latitudes, correct, since the circle is bigger? Is it because a point on a bigger circle is moving faster, and basically chucks things into space faster?
The tangential velocity is greater because every point on the Earth's surface completes the same number of rotations, but the further a point is from the rotational pole, the further it has to travel in that time. Velocity is distance over time, so more distance in the same time means more velocity.
Objects thrown from the surface always retain their tangential velocity (the change is negligible in flights within visual range, but even the larger artillery cannons have to take it into account), so objects launched from points moving faster have more momentum, and thus need less engine burn to get to escape velocity if they travel in the right direction (and more if they go in the wrong one).
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