This is the 9682nd most frequent Korean word.
고구려천문과학관
Goguryeo Astronomy Science Center.
Here, '고구려천문과학관' refers to a proper noun, the name of a specific facility dedicated to astronomical science.
고구려천문과학관은 별자리 관측을 위한 공간입니다.
The Goguryeo Astronomical Science Hall is a space for observing constellations.
In this sentence, '고구려천문과학관' is the location at which an event, namely the lecture, took place.
어제 고구려천문과학관에서 열린 천문학 강의에 참석했습니다.
Yesterday, I attended an astronomy lecture held at the Goguryeo Astronomical Science Hall.
Here, '고구려천문과학관' is mentioned as the possessor of the telescope, emphasizing its linkage to the institution.