一个主要的问题是维持宇航员的身体健康。 医疗救治可能需要几天甚至几个星

A major problem is to maintain astronaut health. Medical treatment may take days or even weeks, because there is no doctor on board possible. Such as appendicitis or ulcer disease, conventional treatment on Earth, in space can be fatal, because the time to see a doctor delayed

A major problem is maintaining the health of astronauts. Medical treatment may take days or even weeks, as there may be no doctoron on board. Diseases such as appendicitis or ulcers are routine lying on Earth and can be fatal in space because of delays in seeing a doctor.

A major problem is to keep astronauts healthy. Medical treatment can take days or even weeks because there may not be a doctor on board. Diseases like appendicitis or ulcers, which are routinely treated on earth, can be fatal in space because of delays in doctor visits