A new Earth observation satellite, Gaofen-3 03, was launched by a Long March-4C rocket from the Jiuquan Satellite Launch Center in northwest China on April 7 and has entered the planned orbit successfully.

　　The satellite has been networked with the orbiting Gaofen-3 and Gaofen-3 02 satellites, marking the formation of China's first land-sea radar satellite constellation, which can capture high-definition, reliable, stable synthetic aperture radar (SAR) images with wider coverage and multiple modes.

　　These images will boast a 1-meter resolution, with a maximum imaging width of 650 km and 20 imaging modes, thereby improving the monitoring capabilities of the country's land-sea radar satellites.

　　Meanwhile, compared with single satellites, the satellite constellation will shorten the average revisit period, which refers to the time elapsed between observations of the same point on the Earth by a satellite, from 15 hours to five hours, said Lin Mingsen, director of National Satellite Ocean Application Service (NSOAS) under the Ministry of Natural Resource.

　　The Gaofen-3 satellites will provide remote-sensing data for marine disaster prevention and mitigation, dynamic marine environment monitoring, marine research, environmental protection, water conservancy, agriculture and meteorology, while helping to safeguard maritime rights and interests.

　　To date, China has launched 12 ocean monitoring satellites. Gaofen series satellites, together with Haiyang-1 satellites monitoring ocean color and Haiyang-2 satellites monitoring dynamic ocean environment, have formed a coordinated ocean observation system, said Liu Jianqiang, deputy director of NSOAS.