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20 August 2018

China’s photo reconnaissance spy satellites are getting better fast

Andrew Tate

A Chinese Earth-observation satellite launched on 31 July from the Taiyuan Satellite Launch Centre may be capable of achieving ground-image resolution of 10 cm or less. If confirmed, this would give China a satellite-imaging capability second only to the United States and possibly comparable to the maximum resolution provided by US imaging satellites. China’s state-owned Xinhua news agency reported that the Gaofen 11 satellite is an “optical remote-sensing satellite” that was carried aloft by a Long March 4B rocket “as part of the country’s high-resolution Earth observation project”. An article in the Science & Technology Daily , the news outlet of China’s Ministry of Science and Technology, noted that the satellite’s ground resolution was “at the sub-metre level”.


Previous Gaofen satellites are part of the civil China High-resolution Earth Observation System (CHEOS). However, Gaofen 11 was not included in previously released information related to the civil programme, so it is likely that this satellite will have a primarily military role.

A video of the launch was released by state-owned broadcaster China Central Television (CCTV), and computer-generated 3D images displayed in the satellite control centre were also shown. These included a representative image of the satellite while still attached to the rocket’s third stage but after the payload faring had been jettisoned.

Analysis of this image published on the website SatelliteObservation.net compared the size of the satellite body with the known diameter of the third-stage module and concluded that the mirror lens is around 1.7 m across.

The satellite has been placed in an elliptical near-polar orbit, which gives it an altitude of 693 km at its apogee and 247 km at its perigee, which occurs at 10:00 h local time at latitude 20° N -– such as when passing over the South China Sea, India, or Hawaii.

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