How to walk in space

  There are three technical difficulties in spacewalking: one is that there is no way to go in space; the other is that astronauts cannot walk on their legs in a weightless state, mainly relying on hands; and the third is that the extravehicular environment is very harsh. If a component fails, it may endanger the safety of the astronauts.
  At 8:11 on July 4, 2021, astronaut Liu Boming successfully opened the exit door of the Tianhe core module node module. As of 11:02, Liu Boming and Tang Hongbo wore a new generation of “Flying” extravehicular space suits independently developed by China and successfully exited from the node module of the Tianhe core module. At 14:57, after about 7 hours of exiting activities, the Shenzhou 12 astronaut crew worked closely together and successfully completed all the scheduled tasks during the exiting activities. The safe return of Liu Boming and Tang Hongbo to the Tianhe core capsule marked the complete success of the first astronauts exiting the space station in my country.
  Why spacewalk
  astronauts Why conduct extravehicular activities? In other words, why do we need to take a spacewalk?
  Simply put, a spacewalk has six main purposes: one is to assemble and expand space stations in space, the other is to repair and maintain spacecraft in space, the third is to recover, maintain and release satellites, the fourth is to complete some scientific research tasks, and the fifth is to carry out. Emergency space rescue, six is ​​manned landing on the moon and manned landing on Mars, etc. Therefore, spacewalking is very important.
  The International Space Station currently in orbit is assembled by astronauts through multiple spacewalks.
  With the development of spacewalk technology, more and more ways of spacewalking. According to the purpose and tasks of the exit activities, it can be divided into four types: the first is the verification type exit activities, the second is the assembly type exit activities, the third is the maintenance type exit activities, and the fourth type is the payload. Kind of out-of-cabin activities, that is, recovery, repair and release of satellites or installation of experimental devices on the lunar surface, collection of lunar rock specimens, etc.
  In 2008, the astronaut Zhai Zhigang carried out my country’s first spacewalk, which was a verification activity. The spacewalk carried out by the Shenzhou 12 astronauts this time is an assembly-type or payload-type out-of-vehicle activity. Due to the long space walk and the complicated extravehicular installation task, the difficulty is much greater than that of Zhai Zhigang’s first space walk.
  How to Train spacewalk
  spacewalk technology is very complex, and therefore must be a lot of training. The most important training is in the sink. Because this method can provide astronauts with a training environment that simulates weightlessness and is the most effective training method.
  The neutral buoyancy tank of the my country Astronaut Center is circular, 23 meters in diameter and 10 meters deep, which is the largest in Asia. During tank training, it is necessary to adjust the counterweight lead block on the astronaut tank training suit so that the astronaut neither floats up nor sinks to the bottom, thereby simulating the operating effects of the weightless environment.
  Through neutral buoyancy tank training, astronauts can experience and proficiently master the motion and attitude control of the body under simulated weightlessness, as well as the characteristics, methods, skills and skills of the operation of out-of-cabin activities.
  Because the spacewalking technology is very complicated, all operations that need to be performed outside the cabin usually need to be practiced about 60 times in the tank. Every time Shenzhou 12 astronauts train in the tank, they wear more than 200 kilograms of tank training suits and train for several hours. Often after training, I’m so tired that I can’t even hold my chopsticks.
  Difficulties children spacewalk
  spacewalk technical difficulties there are three: First, nowhere in space; Second, the astronauts can not use legs to walk in weightlessness, mainly by hand; Third, extravehicular environment is very bad, if extravehicular activity The failure of an important component in the system may endanger the life of the astronauts.
  In fact, most of the time when astronauts take a spacewalk, they move from one working position to another. Therefore, how to effectively move the body during a spacewalk is a very important technology. To move your body in a weightless environment in space, the key is to be slow, to be careful, or not to panic, and to control your body well, not to touch any objects in flight, not to move fast, otherwise it will cause unnecessary rotation…
  Spacewalking is not exactly the same as training in a simulated weightlessness tank. When training in a water tank, the astronauts move slowly because of the greater resistance of the water. However, there is no resistance during a spacewalk, and the astronaut’s movement flexibility is enhanced, so it is easy to lose control. For example, if you screw a screw too hard, people may follow it.
  What dangers have occurred in space walks
  So far, although there have been no casualties during the spacewalk, many dangers have been encountered. One of the most dangerous was when Leonov, the first person on the spacewalk, got out of the cabin in 1965. Due to the failure of the restraint layer of the outer suit, the suit bulged up and almost failed to return to the cabin.
  In the special environment of space, astronauts are prone to space motion sickness, which has a greater impact on space walks. In March 1969, Apollo 9 astronaut Schwekart suddenly vomited while preparing to exit the capsule on the second day of lift-off. He is suffering from space motion sickness, and for this reason, the time for him to get out of the cabin has been postponed. Because if you vomit during a spacewalk, the vomit will float in the helmet and cannot be handled, and may be inhaled by the astronauts into the lungs, causing serious consequences. In order to reduce the impact of space motion sickness, astronauts now generally walk in space only on the third day after ascending to heaven.
  The most common problems are mostly related to the failure of the extravehicular space suit. On July 16, 2013, the Italian astronaut Palmitano almost drowned when he encountered a helmet leak during a spacewalk. Later, he used the safety rope to “pull” himself back into the cabin door of the International Space Station. Therefore, it is very important to have a safe, reliable, lightweight and dexterous outer space suit.