PERSON@1 -LRB- February NUMBER@1 , NUMBER@2 -- April NUMBER@3 , NUMBER@4 -RRB- was an MISC@1 physicist and space activist .

PERSON@2 `` Gerry '' O’Neill -LRB- February NUMBER@1 , NUMBER@2 -- April NUMBER@3 , NUMBER@4 -RRB- was an MISC@1 scientist .
