China's unmanned spacecraft Shenzhou-8 blasted off from the Jiuquan Satellite Launch Center in the northwestern Gobi desert area at 5:58 a.m. Beijing Time Tuesday.
The spacecraft, carried by a modified Long March-2F carrier rocket, is expected to dock with Tiangong-1 space lab module that was sent into space on Sept. 29.
The spacecraft entered its initial orbit, about 200 km high above Earth, some 20 minutes after its launch, according to the command center.
Commander-in-chief of China's manned space program Chang Wanquan announced that the launch of Shenzhou-8 was successful.
The spacecraft has to go through a series of swingbys to catch up with Tiangong-1, or Heavenly Palace-1, which is orbiting Earth at a height of 343 km.
The rendezvous and docking maneuver will take place within two days and the practice will build up experience for further docking with Shenzhou-9 and -10 in 2012 and the building of a permanent manned space station around 2020.
For Chinese orbiter, the chase is on
For the first time, an orbiter China sends into space has a completely new mission: to rendezvous and dock with another one.
The chase spacecraft is expected to catch up with Tiangong-1, or "Heavenly Palace," China's first space lab module within two days after the launch for the country's first docking. The technology is crucial to building a space station.
Before Shenzhou-1 approaches Tiangong-1, it will need to have five orbital changes and four "brakes" during a 1.3-million-km journey.
Tiangong-1, the target orbiter, was lowered to the 343-km-high rendezvous and docking orbit and adjusted itself to fly invertedly on Sunday under the control of the Beijing Aerospace Flight Control Center.
Tiangong-1 has already been in low Earth orbit for more than a month. It was launched into space on Sept. 29.
Chinese space technologists have made "considerable modifications" to previous versions of China's unmanned spacecraft to enable Shenzhou-8 to dock with a target orbiter, a spokeswoman for China's manned space program said on Monday.
"More than half of the 600 or so sets of equipment have been modified, while newly designed devices account for about 15 percent of the total," spokeswoman Wu Ping said.
The modifications were mainly aimed at arming the spacecraft with automatic and manual rendezvous and docking capacities, and to enhance the vehicle's performance, safety and reliability, the spokeswoman said.
"After the improvements, the spacecraft will be able to connect with the target orbiter Tiangong-1 for 180 days," Wu said.
