宇宙飞船就像是一座桥,把地球与空间站连接在一起,否则,空间站就成了大海中的一座孤岛。能担当天地桥梁角色的除了宇宙飞船外,还有航天飞机。而宇宙飞船多为运人的。随着空间站的发展,运货量不断增加,从1978年开始,苏联把“联盟号”载人飞船改装成专门的无人货运飞船,即去掉飞船的环境控制与生命保障、返回着陆和应急救生等载人航天的特设系 The spacecraft is like a bridge connecting the Earth and the space station, otherwise the space station becomes an island in the sea. In addition to the role of bridge between the world spacecraft, there are space shuttle. The spacecraft and more for the transport of people. With the development of the space station, the volume of cargo has been increasing. Since 1978, the Soviet Union has converted the “Soyuz” manned spacecraft into a special unmanned spacecraft, that is, the environment control and life support for the spacecraft is canceled and the landing and Emergency rescue and other manned space ad hoc Department