At
Astatine
Halogen
Astatine is the rarest naturally occurring element on Earth. It is highly radioactive and exists in trace amounts as a decay product of heavier elements.
Key Facts
Atomic Number
85
Atomic Weight
210
State
Solid
Half-life
8.1 hours (At-210)
Discovered
1940
Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè
Overview
Description
Astatine is the rarest naturally occurring element on Earth. It is highly radioactive and exists in trace amounts as a decay product of heavier elements.
Discovery
Astatine was discovered in 1940 by Dale R. Corson, Kenneth Ross MacKenzie, Emilio Segrè.