How many kinds of observatories are there?

The observatory is a building built by people for professional astronomical observation and research. The buildings, instruments and equipment in the Observatory are built and configured according to the needs of astronomical work, and are important places for astronomical exploration.

According to different scientific research purposes, the observatory is divided into three types: optical observatory, radio observatory and space observatory. The main equipment of the optical observatory is various instruments used for optical astronomical experiments, such as sunglasses and optical astronomical telescopes, which are mainly used for the study of azimuth astronomy or astrophysics; Radio observatory is mainly composed of various giant or even super-giant wireless receiving equipment and base stations, such as radio telescopes, which are mainly used for radio astronomy research; Space Observatory is mainly composed of advanced optical observation system, which is mainly used to cooperate with satellites in the air to form an advanced space observation platform.

As early as 2600 BC, the ancient Egyptians established the earliest observatory in the world to better observe Sirius. Similarly, by 2000 BC, the Babylonians set up an observatory for the same reason. China also began to build an observatory about 2,500 years ago, but at that time it was called Taiqing, Mourning and Observatory. In many ancient countries, the observatory is not only a place for observing astronomy, but also a place for divination and sacrifice, so the observatory is generally one of the most important places for rulers.

With the constant changes of the times, the architecture of the Observatory is also constantly changing and improving. The famous observatory in history was established by Danish astronomer Tycho in Copenhagen on 1576, equipped with the most advanced astronomical instruments at that time. The earliest astronomical observatory in China was built in the Yuan Dynasty, and now it is located in Gaocheng Town, southeast of Dengfeng County13km. Guo Shoujing, a famous astronomer in Yuan Dynasty, observed celestial bodies here and calculated an astronomical result: the tropic year is 365 days, 5 hours, 49 minutes and 20 seconds, which is only 26 seconds away from the modern determination of tropic year. The chronicle he compiled was born 300 years earlier than the current Gregorian calendar, which shows that the scientific research level of ancient astronomical calendars in China has been quite superb.

The main purpose of the Observatory is to make it easier for astronomers to observe the sky with telescopes. In order to better let people observe the shape and movement of stars in the sky, observatories are generally built on mountains far away from cities, not because mountains are closer to stars. The stars are far away from the earth. Generally, stars are hundreds of trillion kilometers away from the Earth, and the nearest celestial body, distance to the moon Earth, is 380,000 kilometers away. The mountains on the earth are generally only a few kilometers long, so it is obviously insignificant to shorten such a short distance. This is because the geographical position of the mountain is relatively high, the air is relatively thin, and there is less smoke and water vapor, which has less influence on people's observation of celestial bodies and is more conducive to the smooth progress of astronomers' scientific research. China's famous observatories, such as the Purple Mountain Observatory, are located in the northeast of Nanjing, with an altitude of 267 meters.

Generally speaking, the roof of the observatory is designed as a silver hemisphere. Seen from a distance, the silver-white round roof sparkles in the sun. The reason why it is designed in this form is not for beauty. In fact, the silver dome is the observation room of the Observatory. A huge skylight will be cut in the roof hemisphere, mainly to facilitate people to observe space through astronomical telescopes. Generally, astronomical telescopes are too big to move around. However, observation with astronomical telescope needs 360-degree observation space, and it is difficult to meet the use conditions with ordinary roof astronomical telescope. However, the Observatory adopts a hemispherical roof design and has an extremely wide 360-degree skylight, which fully meets the needs of 360-degree rotation of astronomical telescopes, allowing people to explore and observe the sky directly with professional astronomical telescopes. When not in use, as long as the skylight on the dome is closed, the astronomical telescope can be protected from wind and rain, and it can be completely unaffected by space restrictions.