主焦点观测舱
/ˈpɹaɪm ˈfəʊkəs ɒbzˈɜːvɪŋ ˈkapsjuːl/
n
English: prime focus observing capsule · 主焦点观测舱
English · prime focus observing capsuleEspañol · cabina en el foco primarioFrançais · nacelle d’observation
释义：Area where astronomers once gathered to monitor the exposure time of photographic plates.