( ( ( ( ( Science Objectives ) ( The ( Pioneer 11 ) ) ) and ) ( ( ( Voyager 1 ) and ) ( 2 spacecraft ) ) ) ( ( observed ( Saturn ( in ( 1979 ( , ( ( 1980 and ) 1981 ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (NP (NNP Science) (NNP Objectives)) (NP (DT The) (NNP Pioneer) (CD 11))) (CC and) (NP (NP (NNP Voyager) (CD 1)) (CC and) (NP (CD 2) (NN spacecraft)))) (VP (VBD observed) (NP (NP (NNP Saturn)) (PP (IN in) (NP (CD 1979) (, ,) (CD 1980) (CC and) (CD 1981))))) (. .)))
Science Objectives The Pioneer 11 and Voyager 1 and 2 spacecraft observed Saturn in 1979, 1980 and 1981.
(ROOT (S (NP (DT The) (NN voyager) (CD 1) (NN spacecraft)) (VP (VBD visited) (NP (NN saturn)) (PP (IN in) (NP (CD 1980)))) (. .)))