- Michelson’s wonder was what his head did with his hands, and a few boxes and rotating mirrors. He measured things, especially things that were regarded as unmeasurable, ineffable, and precious as life itself. Among other things, he had measured light and a star. I watched him play billiards nearly every noon for several months before he retired from the University, and, in introducing myself, I could further say with equal truth, “Shake the hand that shook the hand of John L. Sullivan.” If I get the right opening, though, I prefer saying, “When young, I watched Michelson play billiards.”
- Astatine (Wikipedia)
Astatine is a chemical element; it has symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth’s crust, occurring only as the decay product of various heavier elements. All of astatine’s isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours. Consequently, a solid sample of the element has never been seen, because any macroscopic specimen would be immediately vaporized by the heat of its radioactivity.