(美国国家航空航天局)用射电望远镜跟踪小行星TB-145。4、 2:33 Nasa tests enormous rocket booster 2点33分NASA试验了巨大的火箭助推器。5、Watching the skies for asteroids that could threaten Earth
In April 1956, the aviation industry commission of the people's Republic of China was established to lead China's aviation and rocket industry.中国航天史是从1956年二月开始的,当时著名科学家钱学森向中央提出《