When testing different diameter pipeline or vessel, the orbit module is changed only.

检测不同管径的管道时，仅需更换轨道模块。

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Since the orbiter, the Command Module, had already been thoroughly tested, a decision was made in August 1968 to send Apollo 8 into lunar orbit instead.

由于轨道舱和指令舱已经全部测试完成，于是就决定在1968年8月先把阿波罗8号发送到月球轨道。

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The mission was planned as a low-Earth orbit to test the Lunar Module, the lander later used by Apollo 11 and subsequent missions to land on the moon's surface.

他们的使命只是做地球低轨道飞行，以测试月球舱和阿波罗11号以及以后的登月任务所使用的登月舱。

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Eagle moved into the orbit of the command module.

VOA: special.2009.07.15

The astronauts are aiming to complete China's first manned docking with the Tiangong-1 module already in orbit, an important first step towards China's aim of creating a working space station by 2020.

BBC: China's female astronaut quandary

The module will remain in orbit after the mission.

NPR: China Launches Manned Spacecraft

William Safire prepared a eulogy for Richard Nixon to deliver should the lunar module fail to get back up into orbit.

FORBES: Neil Armstrong: Ode to Trustmarks