Assertion: astatine's life | /r/HasProperty | about 8 hours
Facets:
Source sentences:
text: Part of the reason why there has been very little research done on organoastatine chemistry is the extreme radioactivity of astatine; the half-life of $\ce{^210At}$, the longest-lived isotope, is about 8 hours.
text: Astatine was only discovered in 1940, and only about 30 grams (about a teaspoon worth) of it are thought to exist on the entire earth at any one time; and the half-life of the most stable form of Astatine is about 8 hours.