People of Koguryo (B.C. 277 - A.D. 668) had observed the solar eclipse, lunar eclipse and movements of meteors and comets from B.C. And, on the basis of such observed data, they carved an astronomical chart on a stone in the late 5th century- the early 6th century.

This chart presented basic data necessary for understanding of theory and knowledge of astronomy and astronomical observation, thus helping compile a calendar. According to "Haedong Miscellany", a book of the feudal Joson dynasty (1392-1910), the chart was located in the Walled City of Pyongyang, but disappeared in the closing years of Koguryo when foreign aggressors raided into it.

A paper copying the said astronomical chart was discovered in the early period of the feudal Joson dynasty, and "Chonsangryolchabunyajido" (astronomical chart) was made on the basis of this paper in 1395. It has been handed down still now.

"Chonsangryolchabunyajido" was a very scientific and detailed astronomical chart at that time.

Marked on this chart are 1,467 stars in 282 constellations, positions of the vernal and autumnal points, the Milky Way, etc.