Spatial knowledge

Space (English: space) refers to the space outside the earth's atmosphere, the whole space outside the atmosphere. Physicists divide the atmosphere into five layers: troposphere (sea level to 9 km), stratosphere (9-45 km), mesosphere (45-80 km), thermosphere (ionosphere, 80-400 km) and outer atmosphere (ionosphere, over 400 km). ?

About 3/4 of the atmosphere above the earth is in the troposphere, and 97% is below the stratosphere. The outer edge of the stratosphere is the highest limit for an aircraft to fly with air support.

Extended data:

I. Space tourism

Space tourism is based on people's ideal of traveling in space. Space travel provides people with an unprecedented experience. The latest and most exciting thing is to enjoy the beautiful scenery in space and enjoy the taste of weightlessness.

These two experiences can only be enjoyed in space. It can be said that this kind of scene only exists in the sky. The space travel project started on April 30th, 20001year. The first space tourist is American businessman dennis tito, the second is South African millionaire mark shuttleworth, and the third is American gregory olsen. Nie Haisheng is one of them.

Second, spacewalk.

Spacewalk is also called extravehicular activity, that is, the process of astronauts completing various tasks outside manned spacecraft or on other celestial bodies such as the moon and planets.

It is a key technology of manned space flight, and it is an important means for manned space flight engineering to install large-scale equipment, conduct scientific experiments, release satellites, and inspect and maintain spacecraft. To achieve the goal of spacewalking, many special technical supports are needed.

Baidu encyclopedia-space