September 1, 2013 by Rui C. Barbosa - nasaspaceflight.com
Another super-secretive launch took place on Sunday from the Jiuquan Satellite Launch Center as China orbited three satellites under the Yaogan Weixing-17 mission. Launch took place at 19:16 UTC from the 603 launch pad of the LC43 launch complex using a Long March-4C (Chang Zheng-4C) launch vehicle.
This is the Yaogan Weixing-17 mission composed of three satellites. Chinese media refer the new satellite as a new remote sensing bird that will be used for scientific experiments, land survey, crop yield assessment, and disaster monitoring.
As was the case in the last launches of the Yaogan Weixing series, western analysts believe this class of satellites is being used for military purposes.
In particular this mission is similar to the Yaogan Weixing-9 and Yaogan Weixing-16, with three satellites flying in formation like a type of NOSS system.
Being similar to the US counterpart, the triplet comprises an electro-optical surveillance satellite, an synthetic aperture radar (SAR) satellite, and possibly an electronic/signal intelligence satellite.
Designed for locating and tracking foreign warships the satellites will collect the optical and radio electronic signatures of the maritime vessels that will be used in conjunction with other information valuable for the Chinese maritime forces.