( ( ( ( ( ( ( ( Petrology and ) geochemistry ) ( of meteorites ) ) , ) ( origin ( of ( solar system ) ) ) ) , ) ( ( thermal history ) ( of asteroids ) ) ) . )
(ROOT (NP (NP (NN Petrology) (CC and) (NN geochemistry)) (PP (IN of) (NP (NNS meteorites))) (, ,) (NP (NP (NN origin)) (PP (IN of) (NP (JJ solar) (NN system)))) (, ,) (NP (NP (JJ thermal) (NN history)) (PP (IN of) (NP (NNS asteroids)))) (. .)))
Petrology and geochemistry of meteorites, origin of solar system, thermal history of asteroids.
(ROOT (S (NP (NP (NNS Meteorites)) (, ,) (VP (VBN formed) (PP (IN of) (NP (NN split) (NNS asteroids) (CC or) (NN planetary) (NNS rocks)))) (, ,)) (VP (VBP provide) (NP (NP (NNS clues)) (PP (IN about) (NP (PRP$ our) (JJ solar) (NN system))))) (. .)))