Although bismuth-209 is now known to be radioactive, it has classically been considered to be a stable isotope because it has a half-life of approximately 2.01×1019 years, which is more than a billion times the age of the universe. Besides 209Bi, the most stable bismuth radioisotopes are 210mBi with a half-life of 3.04 million years, 208Bi with a half-life of 368,000 years and 207Bi, with a half-life of 32.9 years, none of which occurs in nature
God damn.
Isotopes like bismuth 209 make me wonder whether all elements beyond iron might be radioactive, just with absurdly long half-lives.
I wouldn’t even call it radioactive. It’s more like radiolistless. It’s unstable but managing.
I wish my surface oxidized into rainbows when exposed to oxygen.
How do we know the half-life of those elements?
Half-life means the time until only half of the atoms are left, but we don’t have to wait that long to measure the speed of decay. Just like we can measure the speed of a car, without waiting for it to reach the finish line first.
