The origin of platinum and gold is every bit as storied and exotic as the metals themselves, says astrophysicist Stephan Rosswog of the University of Leicester in England. These precious elements arise during one of the rarest and most violent events in the cosmos: the cataclysmic merger of two neutron stars, ultradense stellar remnants that pack the mass of half a million Earths into a ball the size of Manhattan.
Astronomers have long understood that nuclear fusion in stars creates middleweight elements such as carbon and oxygen, but these reactions cannot create superheavy platinum and gold. Rosswog therefore started investigating the far more intense conditions that arise when two orbiting neutron stars spiral in toward each other. "In the beginning it is a very slow process, lasting 100 million years or more. But the last 100 kilometers [about 60 miles] or so before they merge is violent and fast, lasting ...
