( ( This effect ) ( ( is ( ( ( due ( to ( the bending ) ) ) and ) ( ( focusing ( of ( light ( from ( distant objects ) ) ) ) ) ( when ( it ( ( passes ( through ( ( the ( strong ( gravitational fields ) ) ) ( of ( ( massive galaxies ) ( on ( its way ) ) ) ) ) ) ) ( to us ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT This) (NN effect)) (VP (VBZ is) (UCP (ADJP (JJ due) (PP (TO to) (NP (DT the) (NN bending)))) (CC and) (VP (VBG focusing) (PP (IN of) (NP (NP (NN light)) (PP (IN from) (NP (JJ distant) (NNS objects))))) (SBAR (WHADVP (WRB when)) (S (NP (PRP it)) (VP (VBZ passes) (PP (IN through) (NP (NP (DT the) (JJ strong) (JJ gravitational) (NNS fields)) (PP (IN of) (NP (NP (JJ massive) (NNS galaxies)) (PP (IN on) (NP (PRP$ its) (NN way))))))) (PP (TO to) (NP (PRP us))))))))) (. .)))
This effect is due to the bending and focusing of light from distant objects when it passes through the strong gravitational fields of massive galaxies on its way to us.
(ROOT (S (NP (JJ Strong) (JJ gravitational) (NNS fields)) (VP (VBP are) (ADJP (JJ capable) (PP (IN of) (S (VP (VBG altering) (NP (NP (DT the) (NN rate)) (PP (IN of) (NP (NN time) (NN passing))))))))) (. .)))