Neptunium and plutonium

New elements neptunium (number 93) and plutonium (number 94) were discovered by American physicists by studying bombarded uranium. These were the first transuranium elements discovered, hence their names.
Edwin Mattison McMillan and Philip Hauge Abelson United States 1940
Neptunium and plutonium

New elements neptunium (number 93) and plutonium (number 94) were discovered by American physicists by studying bombarded uranium. These were the first transuranium elements discovered, hence their names.