XICHANG, Oct. 15 (China Space News) -- China sent twin BeiDou-3 navigation satellites into space on a Long March-3B carrier rocket from Xichang Satellite Launch Center in Sichuan Province at 12:23 p.m. Monday.

The satellites entered their planned orbit after flying more than three hours, and will work with the 14 BeiDou-3 satellites already in orbit. The satellites are the 39th and 40th of the BeiDou navigation system, and the 15th and 16th of the BeiDou-3 family.

The satellites and the rocket for Monday's launch were developed by the Innovation Academy for Microsatellites of the Chinese Academy of Sciences and the China Academy of Launch Vehicle Technology, respectively. The launch was the 287th mission of the Long March rocket series.