Manual docking requires astronauts to have a precise judgement on the relative distance between Shenzhou IX and the Tiangong-1 module, a challenge to their capability of coordination, accuracy and psychological stability.

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The docking itself was completed by taikonaut Liu Wang, about an hour and a half after Shenzhou-9 undocked from Tiangong-1.

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After the second docking was completed, Shenzhou-8 separated again from Tiangong-1 and then returned to Earth.

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