CNSA after postponing launch of Gaofen-4 satellite to 30th December 2015 still keeps schedule – last launch in this year we will see in Chinese Xichang satellite center.
Gaofen-4 satellite is scheduled for 30th December 2015. China National Space Administration is developing its program of high resolution imaging satellites (Gao Fen means in Chinese “high resolution”) under established in May, 2010 program called China High-resolution Earth Observation System. Program is developed and managed by The Earth Observation System and Data Center of China National Space Administration; overall purpose is general support in various areas of the economy with detailed imaging. CHEOS program is not only reduced to imaging or remotes sensing satellites. It also utilizes near space, aerial and ground systems. Gathered data will be used mainly by Ministry of Land and Resources, Ministry of Environmental Protection, and the Ministry of Agriculture. Whole constellation of CHEOS satellites is planned to be finished in 2020.
For Wednesday, CNSA is planning launching fifth Gaofen satellite. It will cover with range China, Australia, Japan, India, Korean Peninsula. East Pacific and Indian Ocean will be also in its range. Due this fact and equipping satellite in high resolution camera operating with resolution of 50 m and resolution in infrared of 400 m, satellite will provide accurate imaging data. Satellite has onboard optical system operating in visible light and in infrared providing imaging even during poor weather conditions or in night. Weighing 4600 kg satellite will be put into GEO orbit and will become first Chinese geostationary remote sensing satellite.
First satellite supporting CHEOS program was launched on 26 April 2013 on atop Long March 2D from Jiuquan satellite center. It was Gaofen-1, designed by Shanghai Academy of Spaceflight Technology (SAST) and based on CAST2000 bus. Satellite was designed for imaging in various specters, and was equipped with 2 m panchromatic/8 m multi-spectral camera and additional 16 m multispectral medium-resolution and wide-view camera. Satellite weight was 1080kg, satellite was equipped in two deployable solar arrays providing up to 1278 W of power which could be stored in internal Li-ion battery with capacity of 80 Ah. Satellite was put on orbit 625.3 km x 651.2 km with inclination at 98.0468° for about 8 years of operational life. Launch of next satellite from Gaofen-1 series is scheduled for 2016. In 2014 CNSA launched from Taiyuan space center next satellite on atop of Long March 4B. It was Gaofen-2, based on CS-L3000A bus and utilizing high resolution camera with resolution up to 80 cm in panchromatic mode and up to 3.2 m in multispectral mode. It was quickly hailed best Chinese imaging satellite, almost comparable to Ofek-9 Israeli imaging satellite which is considered as one of the best in the world. Gaofen-4 will remain on 608 km × 630 km and inclination of 98.02° for up to 8 years of operational life. In 2015 CNSA launched two following Gaofen satellites. Gaofen-8 was launched from Taiyuan space center on 26 June 2015 on atop Long March 4B rocket into orbit of 484 km × 493 km, inclination at 97.3°. Satellite was described by official sources as imaging spacecraft; shortly after Gaofen-8, on 14 September 2015, Gaofen-9 was launched from Jiuquan satellite center on atop of Long March 2D rocket. This time it was recognized as basing on Yaogan-2 military satellite and probably utilizing CAST2000 bus. A still main objective for Gaofen-9 was high resolution imaging from orbit of 617 km × 664 km with inclination of 98.01°. Estimated operational life was predicted, just like in previous Gaofen satellites, for 8 years.
Some sources are considering Gaofen-4 as possible to be utilized as military satellite for observing American aircraft carriers. China is not possessing enough conventional power (war ships, aircraft carriers and bombers) to stop number of American aircraft carriers, so is declaring, of course not officially, that ballistic missiles will serve as potential weapon against aircraft carriers. To make it possible it is necessary to build system of early warning system detecting movement of American fleet near China’s territorial waters. Most adequate means to build such system are satellites able to search for war ships and further help in aiming ballistic rockets. It is worth to mention that these are only suppositions and satellite will be generally useful for many different purposes. But still due the lack clear separation between military and civilian space program in China and extreme accuracy of Gaofen-4 it cannot be ruled that it will be used for reconnaissance.