At 0545 GMT on 9 August 2014, the Yaogan 20 (Yaogan Weixing-20) mission was launched by a Long March 4C rocket flying out of the Jiuquan launch site in China. The mission, which contains a main satellite and two subsatellites built by CAST, is believed to be engaged in electronic intelligence (ELINT) monitoring of naval operations. According to past Yaogan ELINT missions, the subsatellites will fly in a 120km triangular formation relative to Yaogan main spacecraft.