20世纪中后期。航天事业获得了很大发展,人类开发出大推力运载火箭、人造地球卫星、人造飞船、航天飞机等航天器,并首次敲开了“广寒宫”的大门,在月球上登陆成功,而且航天器不止一次地在金星和火星上着陆。此外,航天业也为世界经济的腾飞做出了卓越的贡献,几乎所有的人都体会到航天事业给他们带来的切身利益和潜在的利 The middle and late 20th century. The space industry has achieved great development. Humans have developed large-thrust rockets, man-made earth satellites, manned spacecrafts, space shuttles, and other spacecraft. They have also knocked on the gates of the “Snow Moon Palace” for the first time and successfully landed on the moon. The device landed on Venus and Mars more than once. In addition, the aerospace industry has also made outstanding contributions to the take-off of the world economy. Almost all people have realized the vital interests and potential benefits brought about by the aerospace industry.