Geodetic origin observatory

Longitude 108°55 'east and latitude 34°32' North -- this is the geodetic origin of the People's Republic of China located in Jinghe New Town, Xi Xian New Area.

A plaque above the gate reads "Geodetic origin of the People's Republic of China", giving a sense of dignity, but without a towering observatory, it could easily blend in with the surrounding villages.Today, we will reveal the mystery of the geodetic origin of the People's Republic of China.

Revelation 1：Why the origin of national dignity?

Until the founding of the People's Republic of China, China had not yet established a unified geodetic coordinate system and could not even determine the exact longitude and latitude of its territory and territorial sea, which greatly affected its economic development and national defense construction.

Early since the founding of new China, the former Soviet union the introduction of geodetic coordinate system in our country, in Leningrad calculate since the s&p peskov observatory, step by step, lead to our country, establish the "1954 Beijing coordinate system", the national geographic information bureau of surveying and mapping first geodetic surveying party vice captain zhong-hui zhang said that the extension in the former Soviet union the earth away from the origin coordinate system set up after, and topography is not close to our country, cause a large error in the process of surveying and mapping.

With the bad relations between China and the former Soviet Union, the absence of an independent geodetic coordinate system is not only detrimental to national interests, but also to national dignity.Zhang zhonghui said that the establishment of the Chinese people's own starting point of the earth coordinates, became the older generation of surveying and mapping people's biggest wish.Against this background, in 1978, the geodetic origin of the People's Republic of China was built and tried in Jingyang. In 1980, the geodetic origin of the People's Republic of China was officially put into use, and the "1980 Xi 'an Coordinate system" was established.

Revelation 2：Why choose Xi 'an and Settle in Jingyang?

"Geodetic origin is not the geometric center of China, but the artificial origin, which was originally selected between xi 'an, Lanzhou, Zhengzhou, Wuhan and other central cities of the mainland", Zhang Zhonghui said. Lanzhou is located in the narrow valley, which is crossed by the Yellow River.Zhengzhou and Wuhan, slightly to the east, are affected by the floods of the Yellow And Yangtze Rivers.But xi 'an is located in the loess soil structure, geological structure is stable, few mineral resources and flood disasters, the geodetic origin near Xi 'an can ensure security and stability.

Why will jingyang settle down again?Zhang zhonghui said that the Qinling Mountains lie to the south of Xi 'an, which is not convenient for observation and coordinate transfer, while Jingyang is to the north of Xi 'an, which has no large shielding and convenient transportation.

"The Wenchuan earthquake had a great impact on China's geodetic datum and plate stability, but according to the analysis of observation data, it did not have an impact on the stability and accuracy of geodetic origin". Zhang Zhonghui believed that the correctness of choosing Xi 'an and jingyang for geodetic origin was verified during the Wenchuan earthquake.

Revelation 3：Agate damage mark, does it affect the measurement accuracy?

The sign of geodetic origin is located in the basement of the main building. The granite base is inlaid with a circular sign made of agate, inscribed with the words "geodetic origin of the People's Republic of China" on the outside and engraved with a line of "x" on the inside. The geodetic origin of the People's Republic of China is in the center.

However, the geodetic origin mark is not spotless.Reporter observed that agate has a damage mark, whether this will affect the accuracy of measurement?

"There is no need to worry about the accuracy of the measurements being affected," explained Liu Xiaodong, geodetic origin administrator of the People's Republic of China. "Shortly after the geodetic origin was officially opened, the relevant units were taking measurements when the gravity lead fell accidentally and hit the agate, leaving damage marks, but the 'cross' line was not damaged."

Revelation 4：Is it a coincidence that it matches the building baseline of more than 2,000 years ago?

In the geodetic origin, there is a story that has been praised by the world archaeology and surveying circles -- in the Western Han Dynasty more than two thousand years ago, there was a super-long north-south building baseline that coincided exactly with the geodetic origin. Is this a pure coincidence?

Reporter looked at 1995 cultural relics of the magazine, "found in han chang 'an as the center of the western han dynasty in shaanxi province north and south long building baseline" the article says, shaanxi archaeologists discovered a across the west in the guanzhong salty throughout the two cities, large construction sites in the western han dynasty and burial of the architectural baseline, with the ancient chang 'an north-south axis, the textual research, the baseline is the most north qi temple "day" of the western han dynasty, han dynasty are to determine the origin of earth.

"This building baseline coincides with the geodetic origin, but it is purely a coincidence," Liu said, noting that the discovery was not made when the geodetic origin project began construction in 1976.

Revelation 5：How long is the service life?Out of the public eye in 2016

At present, the geodetic coordinate system (geocentric coordinate system) with the origin at the center of the Earth mass is urgently needed as the national geodetic coordinate system in the fields of economic development, national defense construction and scientific research. How long will the "1980 Xi 'an coordinate system" based on the geodetic origin be in use?

To this, Zhang Zhonghui said, there is no fixed number of years, it depends on the speed of scientific progress in measurement.The 2000 national geodetic coordinate system is the latest national geodetic coordinate system in China, which adopts geocentric coordinate system, which is conducive to the maintenance and rapid update of the coordinate system by modern space technology.In contrast, the "1980 Xi 'an coordinate system" is quite outdated.

It is understood that since July 1, 2008, China fully launched the 2000 national geodetic coordinate system, the State Council requirements, by 2016, China will complete the current national geodetic coordinate system to the 2000 national geodetic coordinate system transition.This means that the "1980 Xi 'an coordinate system" based on the geodetic origin will be phased out of public view in 2016.

Revelation 6：How to regenerate in the future?Building geographic information industry park

With the popularization and application of the 2000 national geodetic coordinate system, geodetic origin has basically lost its original role in the fields of economic development, national defense construction and scientific research."It is a memorial of the surveying and mapping era, which is still of popular science value!"Liu Xiaodong told reporters that geodetic origin ticket a 5 yuan, a day can not come a few people, sometimes a day no one, a lot of visitors to the status quo of geodetic origin and its reputation is not consistent, appears too simple and monotonous.

Then, after the "1980 Xi 'an Coordinate system" exits the historical stage, how will the geodetic origin be reborn in the future?It is reported that the Administrative Committee of Xi Xian New Area and Shaanxi Bureau of Surveying and Mapping and Geographic Information have built a geographic information industrial park centered on the geodetic origin of the People's Republic of China, and as one of the leading industries of Jinghe New Town in Xi Xian New Area, it has been incorporated into the overall plan of Xi Xian New Area.It is reported that the GEOGRAPHIC Information Industry Park will rely on the Geodetic origin of China, through geographic information, Beidou navigation mapping and other related products research and development, manufacturing, to create low energy consumption and zero pollution high-tech service industry and strategic emerging industrial park.