ASM
China Plans Hi-res Satellite
Imagery from the satellite will be intended for dual (civilian and military) use, on a similar basis to US satellites such as WorldView and GeoEye. The satellite will be called ZiYuan-3 (Resource-3). It will be launched from the Taiyuan Satellite Launch Centre in northern Shanxi Province on a Long March 4B carrier rocket, according to Xu Deming, director of the SBSM and Vice Minister of Land and Resources. Xu did not disclose the planned launch date.
Once successfully launched, the satellite will operate in a sun-synchronous orbit about 506 kilometers in altitude, and produce seamless imagery of the earth's surface from 84 degrees south latitude to 84 degrees north latitude. The satellite will be used for map updates, land resources investigation and monitoring, disaster prevention and reduction, and would serve the agricultural, environmental, urban planning, traffic and national defence sectors, Xu said.
China began remote sensing in the 1970s with satellites that took pictures on photographic film. The ZY-1 was inspired by Soviet technology. As it took images, the exposed film was dropped back to Earth in canisters as it was used. Although the Chinese have released few images from ZY-1, it is believed to have a resolution of about 10 metres.
Beijing orbited its first high-resolution electro-optical imaging satellite, the ZY-2 in 2000. Its resolution of 3 metres. This was achieved through better optics than those in ZY-1, and because the satellite was placed in a lower orbit.
China successfully put a second ZY-2 in orbit on 27 October 2002. Then, on 6 November 2004, it put ZY-2C in orbit with a Long March 4-B rocket from the Taiyuan Satellite Launch Center in northern Shanxi Province. All three ZY-2 satellites are still in orbit. The third has improved performance and technology in comparison with the first two resource satellites. Ground control for the satellites is at the Xi'an Satellite Monitor and Control Center in northwest China.
