In central Beijing, tucked behind the southwest exit of the Jianguomen subway station, stands a stone platform which rises 14 meters (46 feet) above street level. Surrounded by modern towers and hotels, this ancient structure was the research center for some of the most important scholars of the Ming and Qing dynasties. This is the site of the Ancient Beijing Observatory.
Above is a present-day view of the Ancient Beijing Observatory. Image Credit: China Museums (http://chinamuseums.com)
Built in A.D. 1442 during the Ming Dynasty, the observatory offers unique insight into ancient scientific techniques. Though research at the observatory ceased in 1929, it achieved a world record for 487 years of continuous astronomical observation.
But astronomical research in China dates back much farther than this structure. In 1279, the Chinese astronomers WangXun and Guo Shoujing built a small observatory just north of this location. And before that, during the Song Dynasty (960-1279), astronomers created a catalogue of 1848 stars and 283 constellations. And some research dates even farther back, with some astronomical records dating to the Han Dynasty (206 B.C. to A.D. 220).
Astronomy and astrology have historically played a role in the decision-making and planning of China’s emperors. This is because the ancient Chinese believed there was a relationship between the sky and earth, and that observations in the sky could predict wars and accidents. As a result, astronomical research was relegated to upper-class scholars and selected foreign missionaries, and the observatory was not open to the public.
New emperors often ordered a new calendar to be made. Releasing a more accurate calendar was a sign that the new emperor was truly sanctioned by the heavens. Beginning in the Qing Dynasty, more than 100 calendars were produced. The earliest calendars were based on the lunar orbit, but this was not suitable for farming, so in time the solar orbit was added. This lunisolar calendar helped farmers plan their crops. The year was divided into 24 solar terms which predicted the changing of the seasons. In 1281, astronomer Guo Shoujing calculated that one year was 365.2425 days, 300 years before western astronomers made the same discovery and created the Gregorian calendar. The lunisolar calendar system was used until 1911 when the western solar calendar was adopted.
In addition to tracking movements in the sky, astronomers also tracked the wind, rain and snow, making their practice a combination of astronomy, astrology, and meteorology.
From 1669 to 1674, Emperor Kangxi commissioned the Flemish Jesuit missionary Ferdinand Verbiest (1623 – 1688) to design six bronze astronomical instruments, a celestial globe, the equatorial armillary sphere, the ecliptic armillary, the quadrant, the altazimuth and the sextant (it is not known why Verbiest based these instruments on the outmoded designs of Tycho Brahe, as the research of the day was well into the era of telescopic astronomy). In 1715, Killian Stumpf designed two other instruments—the azimuth theodolite, which is a combination of an altazimuth and quadrant and is used to measure the vertical and horizontal angles and altitudes of celestial bodies. In 1744, Emperor Qianlong ordered the construction of the last astronomical instrument—the new armillary sphere—to be added to the ancient observatory. These instruments occupied the roof of the observatory, while the older instruments were moved to the yard below.
All of the observatory's instruments except the altazimuth theodolite are adorned with bronze dragons at the base, signifying that astronomy was a special discipline for the emperor. A telescope was never added to the collection, although the emperor acquired one and kept it at the palace for personal use. The observatory was raided in 1900 during the Eight-Nation Alliance's siege of Beijing, and the instruments were taken by foreign troops. The French returned five of the instruments the next year, while the Germans took five of them to Europe to display at Potsdam Hall. They were finally returned in 1921. Several of the instruments were sent to Nanjing for safekeeping after the Japanese invaded China.
The site was opened to the public as a museum in 1983. It is operated in conjunction with the Beijing Planetarium and currently receives about 500 visitors per week. There are detailed English descriptions available. In the courtyards surrounding the Ancient Observatory, there are three exhibitions about the history of astronomy in China, the uses of the various instruments and examples of ancient instruments such as water clocks and sundials. Visitors can also climb to the top of the observatory, which has 99 steps to signify a relationship to the emperor. There they can look at additional instruments displayed on the roof.
To learn more about Ancient Beijing Observatory, click here to visit the website of the Beijing Planetarium.
To learn more about Ancient Beijing Observatory, click here to visit China’s travel website.