Why can the rocket fly in space

Why can the rocket fly in space

In the atmosphere, the rocket flight can be based on Newton’s role and the reaction of the theoretical explanation, that is, the rocket backward gas, gas to push the air back, the air will give the rocket to the same size
Reaction to promote the rocket forward.
However, when the rocket flew out of the atmosphere to the space, the air is gone, the air reaction does not exist, then why can the rocket to continue to fly it?.. ?? …. ?? ..
In fact, it is necessary to use Newton’s law to explain this problem, the key is the force and the role of the point of transformation.
During the forward flight of the rocket, the combustion agent and oxidant burned rapidly in the combustion chamber, producing high temperature and high pressure gas that spewed backwards at a speed of several kilometers per second.
We put the rocket and the gas emitted as the interaction of two objects, click on the role of the rocket, the problem is solved.
When the rocket in the jet is equivalent to the gas to a backward thrust, according to Newton’s law, the gas will be emitted through the role of the rocket to the rocket a reaction force, so that the rocket forward.
This physical process has nothing to do with the air, so even in the absence of air space, the rocket will still high-speed flight.