name            launched       vehicle  ceased operation                                              notes
0  injun 1      june 29 , 1961   thor - able    march 6 , 1963  failed to separate from solrad 3 , still in orbit
1  injun 2   january 24 , 1962   thor - able  failed at launch           upper stage produced insufficient thrust
2  injun 3  december 12 , 1962  thor - agena  august 25 , 1968     orbit decay and re - entry on august 25 , 1968
3  injun 4  november 21 , 1964   scout x - 4     december 1966                                     still in orbit
4  injun 5     august 8 , 1968   scout x - 4         june 1971                                     still in orbit
5  injun 6       june 3 , 1974   scout x - 4   april 28 , 1978                         main article : explorer 52

Table as JSON:
{"name":{"0":"injun 1","1":"injun 2","2":"injun 3","3":"injun 4","4":"injun 5","5":"injun 6"},"launched":{"0":"june 29 , 1961","1":"january 24 , 1962","2":"december 12 , 1962","3":"november 21 , 1964","4":"august 8 , 1968","5":"june 3 , 1974"},"vehicle":{"0":"thor - able","1":"thor - able","2":"thor - agena","3":"scout x - 4","4":"scout x - 4","5":"scout x - 4"},"ceased operation":{"0":"march 6 , 1963","1":"failed at launch","2":"august 25 , 1968","3":"december 1966","4":"june 1971","5":"april 28 , 1978"},"notes":{"0":"failed to separate from solrad 3 , still in orbit","1":"upper stage produced insufficient thrust","2":"orbit decay and re - entry on august 25 , 1968","3":"still in orbit","4":"still in orbit","5":"main article : explorer 52"}}