Noun
a highly unstable radioactive element (the heaviest of the halogen series); a decay product of uranium and thorium
Source: WordNetAtomic radii main Atomic number plotted against atomic radius The noble gases, astatine, francium, and all elements heavier than americium were left out as there is no data for them. Source: Internet
A total of 31 isotopes of astatine have been discovered, with atomic masses ranging from 193 to 223. Production Approximately six million metric tons of the fluorine mineral fluorite are produced each year. Source: Internet
A practical application for astatine as a cancer treatment would potentially be suitable for a "staggering" number of patients; production of astatine in the quantities that would be required remains an issue. Source: Internet
Even though astatine is naturally occurring, it is usually produced by bombarding bismuth with alpha particles. Source: Internet
Elemental astatine has never been viewed because any macroscopic sample would be immediately vaporized by its radioactive heating. Source: Internet
Four isotopes of astatine were subsequently found in nature, although it is the least abundant of all the naturally occurring elements, with much less than one gram being present at any given time in the Earth's crust. Source: Internet