BEIJING, Nov. 7 (Xinhuanet) -- Tiangong-1 and Shenzhou-8 have now orbited together for more than 90 hours. In just over a week's time, the two will carry out a second docking if all tests run smoothly.
The second docking will be conducted with poorer orbit and light conditions purposely to test the reusability of the docking systems.
Wang Xiang, deputy chief engineer of Manned Spacecraft System, said, "To make the second docking possible, the two modules need to be first disconnected. And then they will have to be reconnected perfectly. The whole process is new to us."
The Shenzhou -8 is equipped with microwave radar, laser radar and a high-resolution imaging sensors to accomplish the docking. It is also important to test whether radars and sensors can be used under different conditions in the second docking.
Wang Xiang, deputy chief engineer of Manned Spacecraft System, said, "The sensors have different reactions under different conditions. All space engineers will meet this problem. The only way to overcome the problem is to test the sensors in a different orbit in the second docking. This test also adds some uncertainties to the success of the second docking."
The Shenzhou-8 and Tiangong-1 will orbit together for a total of 12 days doing tests. Then a second docking will be followed by two days' flight. Shenzhou-8 is scheduled to return to Earth on November 17th.