(S (S (PP (IN In) (NP (BASENP (DT a) (JJ new) (NN model)) (VP (VBN created) (PP (IN by) (BASENP (NNP NASA) (NNS scientists)))))) (COMMA ,) (S (BASENP (NNS data)) (VP (VBZ shows) (SBAR (IN that) (S (S (BASENP (NNP Enceladus)) (VP (MD might) (VP (VB have) (VP (VBN been) (VP (VBN created) (PP (IN by) (NP (BASENP (NN aluminum) (CC and) (NN iron) (NNS isotopes)) (SBAR (WHNP (WDT which)) (S (VP (VBP have) (VP (VBN begun) (S (VP (TO to) (VP (VB decay) (S (VP (VBG causing) (S (NP (BASENP (JJ large) (NNS amounts)) (PP (IN of) (BASENP (NN heat)))) (VP (TO to) (VP (VP (VB build) (PRT (RP up))) (PP (IN in) (BASENP (DT the) (NN moon)))))))))))))))))))))) (CC and) (S (ADVP (NP (BASENP (QP (RB over) (NNS billions))) (PP (IN of) (BASENP (NNS years)))) (RBR later)) (COMMA ,) (S (BASENP (DT the) (JJ icy) (NN mass)) (VP (VBZ has) (VP (VP (VBN began) (S (VP (TO to) (VP (VB melt) (PP (IN near) (NP (BASENP (DT the) (NN moon) (POS 's)) (NN core))))))) (COMMA ,) (S (VP (VBG causing) (S (BASENP (DT the) (NN water)) (VP (TO to) (VP (VB spew) (PP (IN into) (BASENP (JJ outer) (NN space))))))))))))))))) (PERIOD .))