• they/them

plural system in Seattle, WA (b. 1974)
lots of fictives from lots of media, some horses, some dragons, I dunno. the Pnictogen Wing is poorly mapped.

host: Mx. Kris Dreemurr (they/them)

chief messenger and usual front: Mx. Chara or Χαρά (they/them)

other members:
Mx. Frisk, historian (they/them)
Monophylos Fortikos, unicorn (he/him)
Kel the Purple, smol derg (xe/xem)
Pim the Dragon, Kel's sister (she/her)


most folks know that the gravitational acceleration experienced by objects at Earth's surface is approximately constant; g = 9.81 m/s² is the usual figure in the textbooks. this is a basic fact about the Earth, taught in a myriad classrooms.

I am uncertain how well it's known that this figure is, in fact, variable.

g is only approximately constant. it varies spatially, because the Earth is not uniformly dense and is not a perfect sphere, so the value of gravitational acceleration at Earth's surface isn't the same everywhere, and it changes slightly over time thanks to the slow, massy churnings of Earth's inwards.

furthermore, the Moon exerts a periodic tidal effect on g; the entire Earth changes shape slightly as her Moon orbits around her, and thus the gravitation acceleration at Earth's surface change periodically (q.v. http://www.mines.edu/fs_home/tboyd/GP311/MODULES/GRAV/NOTES/tidal.html).

and something else affects measurements of gravitation acceleration on a period of about 5.9 years (https://phys.org/news/2015-04-gravitational-constant-vary.html) and there isn't actually a very good explanation as to why, though there have been several proposals—the article mentions a few.

I find this all very fascinating...especially when you consider the following unfortunate probability: science education is so superficial these days that a great many persons in technical jobs might not actually know that g isn't really a constant, but changes according to place and time. forgive me for suspecting that programmers, especially, might actually believe that g is fixed at 9.81 m/s² exactly, because that's Science™, just like how "biology" says there's only two sexes. /sarcasm

now I ask myself: are such slight differences in g perceptible by humans? the "rationalists" would scoff and write it off as negligible—they're very good at writing things off as negligible, it's one of their favorite activities as "rational" persons—but I think it's the sort of thing that you might just notice, every now and again. because it'd affect everything; everything would be just a little bit heavier, for real. partly because of the Moon, even though Richard Dawkins would say that astrology is bunk. and you know what a great scientist he is. /s

~Chara of Pnictogen (took the whole of "Octavarium" to write that!)


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