A Long March 4C rocket launched three satellites into orbit Saturday on a clandestine mission that will likely serve Chinese intelligence and military organizations.

A Long March 4C rocket lifts off Saturday with the Yaogan 20 payload. Credit: Xinhua
 
The Long March rocket lifted off at 0545 GMT (1:45 a.m. EDT) Saturday from the Jiuquan launching base in northwest China's Gobi desert, according to the state-run Xinhua news agency.

The launch occurred at 1:45 p.m. Beijing time.

Described by official sources as a single remote sensing satellite, the Yaogan 20 payload was put in orbit by the three-stage, liquid-fueled Long March 4C launcher.

"The satellite will be used to conduct scientific experiments, carry out land surveys, monitor crop yields and aid in preventing and reducing natural disasters," Xinhua reported.

But U.S. military tracking data detected three satellites, plus the Long March rocket's upper stage, attributed to Saturday's launch from China.

The objects are orbiting nearly 1,100 kilometers, or about 680 miles, above Earth in an orbit inclined 63.4 degrees to the equator.

The use of the Long March 4C rocket, the Jiuquan launch site, and the detection of three spacecraft in orbit follows a pattern established on three previous launches in March 2010, November 2012 and September 2013.

Western analysts believe the triplets have a naval surveillance mission. Satellites operated by the U.S. National Reconnaissance Office flying in similar orbits are believed to monitor global naval activity.

Saturday's Long March rocket flight marked the 47th space launch to reach orbit this year and the second for China.

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