Cheomseongdae ( ko, 첨성대;

Hanja Hanja (Hangul: ; Hanja: , ), alternatively known as Hancha, are Chinese characters () used in the writing of Korean. Hanja was used as early as the Gojoseon period, the first ever Korean kingdom. (, ) refers to Sino-Korean vocabulary, wh ...

: , ) is an

astronomical observatory An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysical, oceanography and volcanology are examples of disciplines for which observatories have been constructed. His ...

Gyeongju Gyeongju ( ko, 경주, ), historically known as ''Seorabeol'' ( ko, 서라벌, ), is a coastal city in the far southeastern corner of North Gyeongsang Province in South Korea. It is the second largest city by area in the province after Andong, ...

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korea, Korean Peninsula and sharing a Korean Demilitarized Zone, land border with North Korea. Its western border is formed ...

. Cheomseongdae is the oldest surviving astronomical observatory in Asia, and possibly even the world. It was constructed in the 7th century in the kingdom of

Silla Silla or Shilla (57 BCE – 935 CE) ( , Old Korean: Syera, Old Japanese: Siraki2) was a Korean kingdom located on the southern and central parts of the Korean Peninsula. Silla, along with Baekje and Goguryeo, formed the Three Kingdoms of K ...

, whose capital was Seorabeol, or present-day Gyeongju (

Hangul The Korean alphabet, known as Hangul, . Hangul may also be written as following South Korea's standard Romanization. ( ) in South Korea and Chosŏn'gŭl in North Korea, is the modern official writing system for the Korean language. The let ...

: ). Cheomseongdae was designated as the country's 31st national treasure on December 20, 1962. Modeled on

Baekje Baekje or Paekche (, ) was a Korean kingdom located in southwestern Korea from 18 BC to 660 AD. It was one of the Three Kingdoms of Korea, together with Goguryeo and Silla. Baekje was founded by Onjo, the third son of Goguryeo's founder Jum ...

's Jeomseongdae, which now exists only in historical records, the Cheomseongdae influenced the construction of the Japanese observatory in 675, and Duke Zhou's observatory in China in 723.

Structure

Cheomseongdae stands 9.17 meters high and consists of three parts: a

stylobate In classical Greek architecture, a stylobate ( el, στυλοβάτης) is the top step of the crepidoma, the stepped platform upon which colonnades of temple columns are placed (it is the floor of the temple). The platform was built on a level ...

, or base upon which a

column A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...

is constructed, a curved cylindrical body, and a square top. Midway up the body stands a square window and entrance to the inside of the structure. When viewed from above, Cheomseongdae resembles the Korean

character (Hangul: ), meaning "well." The square stylobate base is 5.7 meters wide and built from a single layer of 12 rectangular stones. From the base to the window, the tower is filled with earth and rubble. The cylindrical body of the tower is built out of 365 pieces of cut

granite Granite () is a coarse-grained (phaneritic) intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase. It forms from magma with a high content of silica and alkali metal oxides that slowly cools and solidifies undergro ...

, symbolizing the number of days in a

year A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hou ...

. However, various historical documents have reported different numbers of stones. Song (1983) cites a 1962 survey of the site by Gyeongju National Museum director Hong Sa-jun, who found 366 blocks. This discrepancy in stone count may be attributed to some researchers including or omitting a stone slab inside the top of the tower and not visible from the outside. The stones are fashioned as annular sectors, meaning each stone takes the shape of a curved or bent rectangle. At the top, there are two tiers of (), and it is presumed that an observation device was placed on it. Its construction style parallels that used at the Bunhwangsa Temple in Gyeongju.

Symbolism

The number and placement of the stones in Cheomseongdae have been theorized to represent various historical and astronomical figures. The central hole or window separates the body into 12 layers of stones both above and below, symbolizing the 12 months in a year and the 24

solar term A solar term is any of twenty-four periods in traditional Chinese lunisolar calendars that matches a particular astronomical event or signifies some natural phenomenon. The points are spaced 15° apart along the ecliptic and are used by lunisolar ...

s. Additionally, the 12 stones which comprise the stylobate may also reference the 12 months. CheomseongdaeModel2

Preservation

Cheomseongdae's original appearance and shape has remained unchanged for over 1300 years; however the structure now tilts slightly to the north-east. In 2007, a system was installed to measure the state of Cheomseongdae every hour. Of particular concern are cracks and structural displacements, and movements of the foundation stones. Cheomseongdae is additionally susceptible to wear due to aging and weathering, particularly from air pollution and structural imbalance caused by ground subsidence. The exterior of the structure is regularly washed down to remove moss. The National Research Institute of Cultural Heritage in Korea has conducted inspections on the structure regularly since 1981. The Gyeongju municipal government oversees the site's management and preservation.

Popular culture

Cheomseongdae is mentioned in the popular

Korean drama Korean dramas (; RR: ''Han-guk deurama''), more popularly known as K-dramas, are television series in the Korean language, made in South Korea. They are popular worldwide, especially in Asia, partially due to the spread of Korean popular cultu ...

Queen Seondeok Queen Seondeok of Silla ( ko, 선덕여왕 ; 595~610 – 17 February 647/January 8, Lunar Calendar) reigned as Queen Regnant of Silla, one of the Three Kingdoms of Korea, from 632 to 647. She was Silla's twenty-seventh ruler, and its first re ...

''. In the 2009 drama, Cheomseongdae was constructed when Queen Seondeok was still a princess; this was her first decree as a princess. Cheomseongdae was meant to share the knowledge of astronomy with everyone, rather than letting one person (Lady Misil) abuse the knowledge of it. By doing so, she also abdicated her divine rights. Because this was uncommon at the time and unsupported by many conservatives, at the opening of Cheomseongdae, barely any nobles showed up.

References

External links