(S (S (NP (BASENP (DT The) (NN aim)) (PP (IN of) (BASENP (DT the) (NNP LRO) (NN mission)))) (VP (VBZ is) (S (VP (TO to) (VP (VP (VP (VB spend) (NP (QP (ADVP (IN at) (JJS least)) (DT a)) (NN year))) (PP (IN in) (NP (BASENP (DT a) (JJ low) (JJ polar) (NN orbit)) (PP (IN above) (NP (BASENP (DT the) (NN surface)) (PP (IN of) (BASENP (DT the) (NN moon)))))))) (S (VP (TO to) (VP (VB gather) (NP (BASENP (JJ neccesary) (NN data)) (PP (IN for) (NP (BASENP (JJ future) (NNS missions)) (CC and) (BASENP (JJR longer) (JJ lunar) (NNS expeditions))))))))))))) (PERIOD .))