I used to have a tee shirt, that had a picture of a garden mole and exterminator. The caption was “Mole problems? Call Avogadro 6.022 x 10^23.”
It’s a chemistry joke.
OK, it’s geeky. Avogadro’s number is the number of atoms in a mole, which allows us to convert the unit of mass to number of atoms, and vice versa, by converting the atomic number to grams. Carbon 12 (the most common carbon isotope) is the reference–a mole of carbon 12 atoms will, in theory, mass exactly twelve grams. Similarly, a mole of hydrogen atoms will mass one gram.
Obviously, for this to work, we have to know pretty accurately just how many atoms there are in a mole. In fact, if we knew it accurately, and precisely enough, we could use it as an atomic basis for mass (just as the meter was defined in terms of wavelengths of a specific chemical laser, and more recently as the distance light goes in a certain time interval measured by a cesium clock). The current (crude) standard for mass is a lump of metal, a kilogram by definition, kept in a bell jar in Paris.
Recent research indicates that the traditional number, first identified by Avogadro, may be a little off. If they can refine the number sufficiently, it can be established as the basis for mass, and we can free ourselves of one of the few areas in which we’re dependent on the duplicitous French…
Hey, you think you’ve got it bad?
Go hence and read about the worst jobs in science.
[Update at 12:40 PM PDT]
Here’s a blog-relevant one:
Yes, astronaut. By many lights, being an astronaut is the best job in the solar system, though one that carries with it the ultimate risk. But set aside the mortal danger and it’s still a job of great frustration, self- sacrifice, even debasement. Astronauts are subjected to the most arduous of tasks: sitting in high-G centrifuges so that doctors can study motion sickness, deliberately enduring hypothermia for hours on end, wearing rectal probes and central IV lines in all forms of stress training like so many guinea pigs (though?mitigating factor?no shaved bellies). Shuttle and Mir veteran Norm Thagard once objected to a study designed to make him wretchedly sick. NASA’s response? “They said I could be fired for good cause, bad cause or no cause,” says Thagard, “but I was required to participate as a condition of employment.” Thagard also had the distinction of being the first person ever to clean out animal cages in orbit, on the Spacelab 3 in 1985. Engineers promised him that the cages would be at negative pressure, so none of the weightless waste of 24 rats and 2 squirrel monkeys would escape. But when Thagard opened the cages, air rushed outward, leading to a frantic floating-feces chase scene. A day later, at the other end of the craft, commander Bob Overmeyer was accosted by a truant turd.
Some of the latest thinking about T. Rex was that it was a scavenger of carrion, rather than a predator.
“I believe it was a scavenger pure and simple because I can’t find any evidence to support the theory that it was a predator,” paleontologist Jack Horner said at the opening on Thursday of “T-Rex — the killer question.”
Horner, the inspiration for scientist Alan Grant — played by Sam Neill — in Steven Spielberg’s “Jurassic Park,” said the lumbering giant was too slow, its arms too small and its sight too poor to catch anything moving.
Another fact from childhood down the drain. Fantasia will never be the same.
[Update on Friday at 4 PM PDT]
Reader (and Transterrestrial site designer) Bill Simon points out this discussion on the subject raging in the comments section.