(S (S (S (BASENP (NNS Particles)) (VP (VBD were) (VP (VP (VBN injected) (PP (IN into) (BASENP (DT the) (NN ring)))) (PP (IN at) (NP (NP (BASENP (RB around) (NN 1500)) (BASENP (NN GMT))) (PP (IN on) (BASENP (NNP Friday)))))))) (CONJP (COMMA ,) (CC and)) (S (PP (ADVP (RB just)) (PP (IN after) (NP (BASENP (NN 1930)) (BASENP (NN GMT))))) (S (BASENP (DT the) (JJ first) (VBN completed) (NN circuit)) (VP (VBD was) (VP (VBN confirmed)))))) (PERIOD .))