航天飞机是20世纪最伟大的科技成果之一。从1981年美国发射第一架航天飞机至今,全球已有六架航天飞机遨游过太空。这六架航天飞机中,有五架是美国制造的载人航天飞机,一架是前苏联于1988年11月发射的无人驾驶 The space shuttle is one of the greatest technological achievements of the 20th century. Since the United States launched its first space shuttle in 1981, six space shuttles have been used in space around the world. Five of the six space shuttles are manned spacecraft manufactured by the United States and one is a pilotless vehicle launched by the former Soviet Union in November 1988