( ( ( ( ( Infrared telescopes ) , ) ( which ( ( includes most ) ( ( ( major ( optical telescopes ) ) ( as ( well as ) ) ) ( a ( few ( ( dedicated infrared ) telescopes ) ) ) ) ) ) ) , ) ( ( need ( to ( be ( ( ( chilled ( with ( liquid nitrogen ) ) ) and ) ( shielded ( from ( warm objects ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NP (JJ Infrared) (NNS telescopes)) (, ,) (SBAR (WHNP (WDT which)) (S (VP (VBZ includes) (ADVP (RBS most)) (NP (NP (JJ major) (JJ optical) (NNS telescopes)) (CONJP (RB as) (RB well) (IN as)) (NP (DT a) (JJ few) (ADJP (JJ dedicated) (JJ infrared)) (NNS telescopes)))))) (, ,)) (VP (VBP need) (S (VP (TO to) (VP (VB be) (VP (VP (VBN chilled) (PP (IN with) (NP (JJ liquid) (NN nitrogen)))) (CC and) (VP (VBN shielded) (PP (IN from) (NP (JJ warm) (NNS objects))))))))) (. .)))
Infrared telescopes, which includes most major optical telescopes as well as a few dedicated infrared telescopes, need to be chilled with liquid nitrogen and shielded from warm objects.
(ROOT (S (NP (NN Liquid) (NN nitrogen)) (VP (VBZ is) (VP (VBN used) (PP (IN for) (NP (NP (VBG cooling) (NNS detectors)) (PP (IN of) (NP (JJ infrared) (NNS telescopes))))))) (. .)))