(S (S (BASENP (NNP NASA)) (VP (VP (VBZ is) (ADVP (RB currently))) (ADJP (JJ unsure) (SBAR (IN whether) (S (BASENP (DT the) (NN problem)) (VP (VBZ relates) (PP (TO to) (NP (NP (BASENP (DT the) (NN sensor)) (COMMA ,) (NP (BASENP (DT the) (NN instrumentation) (NNS circuits)) (VP (VBG reporting) (NP (BASENP (DT the) (NN sensor) (POS 's)) (NN state))))) (CONJP (COMMA ,) (CC or)) (BASENP (DT the) (NN simulation) (NNS circuits)))))))))) (PERIOD .))