If the weather is accommodating wherever you happen to be today, it’s a good day to venture outside, find a patch of grass or forest, lean down, and say loudly, directly into the ground, “CONGRATULATIONS!” The sound will carry through the earth and with luck, will be appreciated by some tiny, burrowing mammals. Because today is Mole Day!
No, wait, it really is Mole Day…but not that kind of mole (they probably wouldn’t appreciate all the shouting anyway). It’s a day to celebrate the number of particles in one mole of material. That’s because the Avogadro number, which is a proportion, not a count, is 6.02×10^23, and at least in the American manner of date notation, today is 10/23. Really we should have celebrated at 6:02 in the morning, but there’s no point going to extremes.
The Avogadro number is named after Amedeo Avogadro, an Italian scientist in the early 1800s. His theory, out of which the number came, was that if you have a quantity of any gas at a given temperature and pressure, it will have a certain weight depending on what kind of gas it is. That weight, he supposed, corresponded to the weight of the particles the gas is composed of, and hence, how many of them there were. Today we would distinguish between atoms of an elemental gas like hydrogen and molecules of a compound gas like air, but in Avogadro’s time the difference between atoms and molecules wasn’t very clear. In fact he didn’t even use the word “atom” — but he did have the general idea that there were “elementary molecules” (atoms) and complex molecules. He could tell there was a third type of “molecule” too; now they’re called ions.
Besides his number, Avogadro pretty much came up with all the basics of atomic-molecular theory, and countless computations in chemistry and physics are based on his work. James Ussher’s calculations, though, had nothing to do with Avogadro, molecules, pressure, or anything else we’d call scientific. While this is ostensibly due to Ussher living two centuries before Avogadro, I’m pretty sure he would have ignored all that molecular stuff even if it had been available.
Ussher was the leader of the Church of Ireland in the 1600s, and was really an early expert in the kind of numerological interpretation that William Miller did to predict that yesterday, October 22nd, was supposed to be the anniversary of the end of the world. Not that yesterday would have happened if he’d been right, but never mind that. Instead of predicting the end of the world by making arcane calculations from Bible verses, though, Ussher decided when the world must have started. And his conclusion was that it started today, October 23, in 4004 BCE. Or possibly the night before, making October 23 the first full day. And of course it was no coincidence that Miller’s prediction was for the world to end around the same time of year. It’s probably to Miller’s credit, though, that when his prediction flopped, he thought the mistake was in his own work. Others making similar predictions have blamed Ussher for mistakes like miscalculating that when it says “day” in the Bible it means “year” (or sometimes something else), or choosing the wrong ancient story about the length of something like the big flood that Noah survived (there are several versions to choose among).
Predictions and other calculations of those sorts often incorporate real-world events, but only the ones they consider significant. It’s a fairly arbitrary process, not too different from how something like the first National Women’s Rights Convention in the US having started on this day in 1850 —and thus it’s included in this very commentary, but you’d never expect to see any mention of this also being the anniversary of the rocket car Blue Flame setting the land speed record in 1970. I mean, you’d definitely never see that sort of thing here, right?
Or even if you did find out about the Blue Flame, which was driven by Gary Gabelich, you’d probably never find out that the name of the car came from the actual color of the rocket exhaust. It was powered by liquid natural gas, and that was because the whole operation was sponsored by the American Gas Association. Unlike many speed record seekers, who often tended to design and build their vehicles as well as piloting them, Gabelich was just the driver. He’d had an interesting career up to that point; he got a job in the mail room of North American Rockwell in the 1950s and worked his way up to test astronaut for the Apollo program. He never flew in space; the job of a test astronaut was to occupy the space capsule while it was tested in every way they could think of short of actually launching it.
Something you might find out here would have to do with a conjunction between the study of pressure, using Avogadro’s number, airplanes, which depend on various aspects of gaseous pressure to work, and October 23. The connection is that not only is October 23 famous for understanding things about gases like air, but it’s also the day, in 1906, that the first airplane flight in Europe took place, piloted by Alberto Santos-Dumont. And not only that, but just five years later (to the day!) it’s the anniversary of the first use of an airplane in a war — the Italo-Turkish War, to be specific.
The secret, you see, is that while the information included here is pretty random, it has to all be connected in some way, and it also has to be sort of generally interesting and not too extreme. There are plenty of atrocities available to go into detail about, but who needs that? This is more like the kind of infotainment you get in a late-night talk show. You know, the kind pioneered and led for decades by Johnny Carson of the Late Show. But you have to decide for yourself whether Carson is listed here because you’re reading a text version of a late-night talk video, or because today is his birthday.
