It is reported that this is the first spacecraft in the on orbit construction stage of China's space station. will provide material support for the six-month on orbit stay of the three astronauts of Shenzhou 14 crew and the assembly and construction of the space station**
According to @ our space official's Micro introduction, it can be seen in CCTV's live camera that bursts of white "smoke" are enveloping the launch tower, which is a normal phenomenon after the rocket enters the filling stage**
The Long March 7 rocket uses liquid oxygen and kerosene propellants.
For liquid oxygen, the rocket at normal temperature is a high-temperature body. If liquid oxygen is forcibly injected into the rocket at one time, the effect will be like pouring cold water into the stove for instant gasification, which will bring great risks to the rocket storage tank.
Therefore, when filling, the rocket will generally be filled with small flow first, gradually cool down and cool down the rocket, and then turn to the stages of large flow filling, deceleration filling, parking and replenishment, and then the rocket will be launched.
During filling, liquid oxygen will be discharged while adding. When the water vapor in the air meets the discharged low-temperature oxygen, it will form water vapor, which looks like "smoke", which is actually the same effect as when we eat popsicles in hot weather
