Frederick Soddy

Frederick Soddy 2 September 1877 - 22 September 1956 was an English radiochemist who explained, with Ernest Rutherford, that radioactivity is due to the transmutation of elements, now known to involve nuclear reactions. He also proved the existence of isotopes of certain radioactive elements. He received the Nobel Prize for Chemistry in 1921, and has a crater named for him on the far side of the Moon.