Qinhai Observation Station, PMO, CAS

Qinhai observation station is located in Delinha, the third largest city of Qinhai Province on the beautiful Tibetan Plateau at approximately 3200m elevation with latitude 32°44'.4N and longitude 97°33'. 6E. Founded in the earlier 1980s, it is also called Delinha observation station.

Xuyi Observation Station, PMO, CAS

Xuyi Observation Station (XOS) is an astronomical observatory operated by PMO in Xuyi County, Jiangsu Province. The station is located on Paoma Mountain, a 180 m peak in the Tieshan Temple National Forest on the boundary of Jiangsu and Anhui Province, with longitude 118°28′E and latitude 32°44′N.

Yao'an Observation Station, PMO, CAS

Yao'an observation station is located in the West Lake Peak, Yao'an, Yunnan province, and belongs to the Purple Mountain Observatory (PMO), CAS.Yao'an station was started to built in Aug 2008, and the first phase of Yao'an observation station was completed in June 2009.

Honghe Observation Station, PMO, CAS

Honghe Observation Station was founded in June 2003 and is located in Honghe farm, which is in the Sanjiang Plain, the eastern part of Heilongjiang Province.

Ganyu Observation Station, PMO, CAS

Ganyu solar observing station is located at Ganyu county, Jiangsu province. It is very near Lianyungang city, one of the most important city in north Jiangsu province. Because of its latitude, the climate condition of Ganyu county is similar to the one in North China. It can be called a Sun shine county of Jiangsu province. In most years, the Sun shine hours exceed 2200. Also, seeing condition around the observing site can be about 1 arcsec.

Qingdao Observation Station, PMO, CAS

Located on the top of the beautiful Guanxiang Mountain in Qingdao city (Latitude:120°19', Longitude 36°04', Altitude: 75 meter), Qingdiao observation station is one of the earliest modern astronomical observation stations in China.

Theodolite Horizon

As a duplicate made by the Qing Government in the early 20th century, this instrument was used for the determination of the coordinates of celestial bodies.

Celestial Globe

Also known as Hun Tian Yi or Hun Xiang in antiquity. Zhang Heng (A.D. 78—139 ) of the Eastern Han (A.D. 25—220), Wang Fan (about A.D. 250) of the Three Kingdoms (A.D. 222—280), and Qian Le-zhi (about A.D. 440) of the Liu Song Period (A.D. 420—479) had once engaged in building a similar instrument, which was aimed to show the location of stars and constellations, and to demonstrate the daily motion of celestial bodies. As the Eight-Power Allied Forces invaded Beijing in 1900, the Ancient Observatory there was looted and most ancient astronomical instruments were taken away. This Celestial globe was duplicated by the Qing (A.D. 1644—1911) Government in 1903.

Armillary Sphere

One of the important instruments for determining positions of celestial bodies in ancient China. This instrument was made in 1437 (Ming Dynasty). It consists of three ring systems, from which the equatorial, ecliptic and horizontal coordinates of celestial bodies could be measured. On those rings both scales of 365.25 and 100 divisions were graduated. These kinds of scale systems possess distinguishing features of ancient astronomy of China. It was pillaged by German troops when the Eight-Power Allied Forces invaded Beijing in 1900. It was returned to China in 1920.

Abridged Armilla

It was simplified and improved by Guo Shou-jing (1231-1316), on the basis of Armillary Sphere. It was used to measure both the equatorial and horizontal coordinates of celestial objects without interference caused by multiple rings. A sundial was added for time keeping during the day time. The instrument was made in 1437. It was looted to French Legation in 1900 when the Eight-Power Allied Forces invaded Beijing. It was sent back to China in 1905.

Gnomon

Gnomon is the most ancient astronomical instrument. It had been used as early as in the period during the Yin-Zhou Dynasties (about 3000 years ago) in China. The horizontal plate lying along the south-north direction is named "Gui" whereas the vertical pole standing straightly to the south of "Gui" is known as Biao. At noon time, Biao would project its shadow on the central line of Gui. The length of the shadow would be the longest on winter solstice and the shortest on summer solstice. Therefore one could determine the solstices and the rest of the Chinese twenty-four solar terms from the length of its changing shadows. In addition, according to the various periods of the shadow length, the number of days in a tropical year was also obtained (365.25days).