什么叫航空、航天和航宇? 对于航空,大家已非常熟悉了,那就是利用气球、飞艇、飞机和直升机等航空器,在地球大气层内的航行活动。 冲出大气层,到广阔的宇宙空间去活动,那就是航天、航宇或者宇宙航行了。 我国著名科学家钱学森认为,人类冲出地球大气层,进入宇宙空间活动,即宇宙航行,简称宇航,其历程可以分为两个阶段。第一阶段为航天,就是在可感知的地球大气 What is aviation, aerospace and aerospace? For aviation, we are already very familiar with that is the use of balloons, airships, aircraft and helicopters and other aircraft in the Earth’s atmosphere in the sailing activities. Out of the atmosphere, to the vast space to go to activities, that is space, aerospace or spacecraft. Qian Xuesen, a famous scientist in our country, believes that mankind has stepped out of the Earth’s atmosphere and entered space activities, namely space flight, referred to as space flight. Its history can be divided into two stages. The first stage is aerospace, that is, the Earth’s atmosphere can be perceived