The first spacewalk of Chinese astronauts on the Tiangong space station lasted nearly 7 hours and achieved great achievements. The moment Liu Boming stepped out of the hatch, he issued "Wow! It's so pretty outside! "The admiration has made countless Chinese people proud.
But did you know that spacewalking is never a romantic and happy job, on the contrary, the space around us is full of dangers, astronauts will encounter danger at any time in the process of working out of the capsule, which may endanger lives in severe cases, and need to be prepared for emergencies at all times.
Chinese astronauts exit the capsule station on the robotic arm
On March 18, 1965, Soviet cosmonaut Alexei Leonov left the Ascendant 2 spacecraft and floated in space for 12 minutes, becoming the first person to "walk in space". When Leonov was preparing to return to the spacecraft, he ran into a big trouble, because the spacesuit expanded in a vacuum, he could not squeeze into the narrow hatch, and finally had to deflate the spacesuit to decompress before returning to the spacecraft. The Soviets trumpeted the first spacewalk, but did not say anything about Leonov's jamming.
The first person to walk in space almost couldn't go back
On June 3 of the same year, Edward White completed the Americans' first spaceflight mission, and the Gemini spacecraft hatch was large enough that the Americans did not need to worry about getting stuck. But when he was preparing to return from outside the Gemini 4 spacecraft, he found that the spacecraft's hatch could not be closed. Just as White was closing the hatch with all his might, Commander James W. White, who was on duty in the return capsule, was on duty. A. McDivitt received orders from the Ground Control Center to abandon the orbital module and White if necessary and sail back to Earth alone. Fortunately, White finally overcame the vacuum cold welding, successfully closed the hatch, and saved his life.
American astronauts can't close the door
Although the Soviets were the first to go into space and the first to complete the feat of human spacewalking, the United States had more extravehicular activities than the Soviet Union and later Russia, and of course they encountered more troubles, but these troubles were nothing compared to edward White's inability to close the hatch.
White escaped, but he was unlucky, and a year and a half later, he and two other astronauts were burned to the ground because of a fire in the Apollo I command module.
Technically, all space activities, including extravehicular walking, are a process of accumulating experience, and whoever encounters the problem will learn from the next mission to ensure that the mistakes of the past are not repeated. But space flight is a high-risk profession, and accidents can happen at any time. In 2013, Italian cosmonaut Luca Parmitano was wearing an American spacesuit during a routine extravehicular repair mission on the International Space Station, causing a large amount of water to pour into his helmet due to dirty things blocking the cooling water system.
The Italian astronaut almost drowned
When astronauts fly in orbit with the space station, gravity is barely felt here due to the acceleration generated by inertia and the acceleration of gravity, so water does not "flow downwards". The water that poured into his helmet stayed inside, gradually covering Luca's nose, eyes and ears, he couldn't hear sounds, couldn't see things, and more dangerously, it was difficult for him to breathe through his nose! Luca immediately decided to return to the airlock, time is life, and if he slows down, he will drown.
Luca's spacesuit had another water leak in 2016, and the water once again poured into the helmet, and American astronaut Copra, who already knew what happened to Luca, decisively aborted the mission and returned to the space station.
Flying extravehicular spacesuit
Extravehicular spacesuit is extremely complex and sophisticated space equipment, it is like a miniature manned spacecraft, to provide security for astronauts, if the spacesuit itself is not safe, it is not possible to talk about the safety of spacewalking. Chinese astronauts understand this, and there are a lot of lessons learned from foreign countries over the years, so there will be no problem with the quality of Chinese spacesuits.
But this does not mean that the spacewalk of Chinese astronauts is absolutely safe and can sit back and relax.
In order to get rid of the shackles of the safety rope, NASA once invented the space jet propulsion technology of the spacesuit, through several nozzles installed on the backpack of the spacesuit life support system, spraying compressed air in different directions, astronauts can freely control their posture, and even fly far away from the spacecraft and fly back.
Astronauts capture satellites from a distance
But then NASA found that this technology is too advanced and too risky, the slightest mistake will drift farther and farther, the oxygen and water in the spacesuit are limited, and drifting away means death. Eventually, the International Space Station phased out the jet suit scheme and returned to the old road of safely tying cables.
The first action out of the cabin is to fix the safety rope
China's cabin departure activities are no exception, Tang Hongbo has to fasten two safety ropes on the armrest of the bulkhead every step forward, move one of the locks forward and move the body, and then loosen the other safety rope buckle and move forward, so that each step is very slow, but at least it can ensure that it will not drift away because of mistakes.
Tang Hongbo has double insurance
But the biggest threat in space often comes unexpectedly, and that is the ubiquity of microflats and space junk. There are countless tiny objects scattered in the space around our earth, which may be just dust and Xiaoice particles from comets, most of which are only the size of sesame seeds, but their speed relative to Earth is often more than 12 km / s. Due to their extremely fast speed, their kinetic energy is very large and their penetration is extremely strong.
In order to resist the impact of micrometers, the outermost layer of the extravehicular spacesuit uses a high-strength aramid fiber, and a multi-layer structure is also used inside to absorb and consume the energy of the micrometers bit by bit. Even so, as soon as it is hit by a meteor, the spacesuit will immediately leak air. The spacesuit relies on oxygen to pressurize the astronauts inside, and once the pressure is lost, the liquid in the human body will boil and expand, and the astronauts will die within ten seconds. Therefore, when the pressure sensor inside the spacesuit senses that the pressure is too low, it will immediately alarm and notify the astronauts to return to the space station as soon as possible.
Warning device on the helmet-faced window
The first mission of the Chinese space station drilled the emergency return procedure, in order to verify the process of astronauts returning to the airlock module in an emergency, from the results, Tang Hongbo spent 10 minutes along the small column of the capsule arm "crawling" for more than ten meters, this speed to deal with the small air leakage problem is not big, but if the air leakage is more serious, the astronauts may not be able to persist for so long.
The spacewalk seems romantic to the spectators sitting on the ground eating melons, and we all yearn for the shock of hovering in space overlooking the earth. But for astronauts in space, extravehicular activities are full of dangers and challenges all the time, and from the moment they step out of the hatch, they are gambling their lives to work. Astronauts are a great group of people, let us salute them and wish them peace and triumph!
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