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China is transferring two of its Long March II F or CZ-2F carrier rockets to their launch site in the west of the country. This is the first time that two CZ-2F rockets are being transferred to the launch center at the same time.

One of the carrier rockets is scheduled for launch in the third quarter of this year to send the Tiangong-2 space laboratory into space. The other carrier rocket will lift off later carrying two astronauts to dock with the space laboratory and embark onto the Tiangong-2.

During their planned 30 day stay at the space laboratory, the two Chinese astronauts will carry out a variety of scientific research and applications, testing some key techniques and exploring the possibility of long-term human residence in space.

Jing Muchun, chief commander of CZ-2F rockets explains:

"Let's put it this way; it's the start of the final battle of the mission of Tiangong-2 space laboratory. We are going to complete the en-masse lifting and thorough checking of the rocket, upon its arrival at the launch center. The rockets have to be sent into space without a hitch, hidden or otherwise. This is our ultimate goal."

Compared with their immediate predecessors launched in 2011, only a few improvements have been made on the new type of CZ-2F rockets, which experts say indicate the maturity of the techniques and technology used on this rocket.