I have been told that this is where Marco Polo looked to the stars when he was in Beijing. Luckily it was right next door to the hotel I stayed at (the Gloria Plaza).
You can visit it, the picture here doesn't show anyone because of how early in the morning it was taken.
There really isn't muc to it, it is a large stone building. But with the right person showing you around, you will get some good stories.
The Beijing Observatory was built in 1437 to 1446 by the Jesuits. Its official name is Exhibition Hall of Ancient Astronomical Instruments and it is the descendent of an observatory first built in 1279 in the Yuan Dynasty. This was the work place of Guo Shoujing, the noted astronomer, hydraulic engineer and mathematician. There are lots of astrological instruments displayed on the roof and inside.
Inside the Observatory, there are many equipment but the museum does not provide good description of how the equipment were used. However, the quiet couryard inside the observatory is a good place to rest and relax.
The Jesuit observatory - won't take long to see but the little museum is interesting and there's a decent view from the top. The ancient instruments are pretty interesting. Also interesting how little mention of the Jesuits is made in the signs - a bit of propaganda, no?
The Hall where the Emperor carried out the annual rituals of Prayer for Good Harvests stands on a three tiered marble mound similar to the Round Altar in the southern par of the park. The three circular roofs are supported by 4 central pillars related to the 4 cardinal points of the earth, an inner row of 12 pillars said to symbolise the months of the year and an outer one supposed to represent the day broken into 12 two hour watches.
Beijing Ancient Observatory:its a small and quite place located in the most busy part of beijing, JianGuoMen. if you dont read those introductions, maybe just take 20mins to walk around the whole area. but if you have patience to read all the introductions, that would be much more interesting.
This Observatory was built in 1442 and is one of the oldest in the world. It is located in part of the old Ming Dynasty city wall that once encircled Beijing, on a raised platform. It served the Ming and Qing astronomers in their star-gazing reports for the Emperor. As he was considered the Son of Heaven, the movements of the heavenly bodies were an important affair. The instruments on display include an Armillary, Celestial Globe, Ecliptic Armilla, Azimuth Theodolite and Sextant.
This historical site was right across from my hotel. Ancient Chinese astronomers kept a close watch on the sky to time festivals.