Michigan astronomers discover promethium in star


  • Anonymous


A rare element that does not exist naturally on earth has been identified in the spectrum of a star by two University of Michigan astronomers.

Working under a National Science Foundation grant, Margo Friedel Aller and Charles Cowley have identified promethium in an unusual star known as HR 465. Promethium is a short-lived rare earth that previously has been known only as a synthetic element. Although its existence had been predicted as early as 1902, it was not discovered until 1947, among the fission products of uranium.