How to avoid "breaking defense" in space? Astronauts' "second skin" can help

As my country's manned space program continues to advance, people have witnessed exciting milestones in the space industry. From the construction and maintenance of space stations to lunar exploration programs, different missions face different challenges and risks, which require different space suits to protect the lives of astronauts. They are like the second skin of astronauts, providing the most solid protection in the extreme space environment, opening a new chapter in human exploration of the universe.

China's extravehicular space suit's journey to space

On September 27, 2008, Chinese astronaut Zhai Zhigang conducted his first spacewalk. In space more than 300 kilometers from the earth, the first extravehicular space suit "Feitian" developed by China made its stunning debut, marking that my country has become the third country in the world to independently master the technology of extravehicular activities. On July 4, 2021, astronauts Liu Boming and Tang Hongbo successfully exited the Tianhe core module node module wearing the new generation of "Feitian" extravehicular space suits independently developed by China. As an important equipment for carrying out China's space station mission, the "Feitian" extravehicular space suit has a unique design concept.

Astronaut Liu Boming successfully exits the spacecraft wearing the new generation of "Feitian" extravehicular space suit

The "Feitian" extravehicular space suit is divided into six layers from inside to outside, including a comfort layer, a backup airtight layer, a main airtight layer, a restriction layer, a heat insulation layer and an outer protective layer. It has important functions such as radiation protection, temperature regulation and pressure regulation, and also has a complete life support system.

"Feitian" extravehicular space suit

The design of the "Feitian" extravehicular space suit is very clever. It is heavy but not bulky, and it is flexible. The bionic structure is cleverly used to make the joints move more freely. Airtight bearings are used at all joints of the upper and lower limbs, allowing the astronauts' hands and feet to move freely while strictly ensuring airtightness. Its backpack is a sealed door for wearing and removing the space suit. Extravehicular space suit life support equipment is installed inside, and spare oxygen bottles are installed at the lower end of the backpack shell. The backpack is closed by tightening the steel cable and operating the closing handle.

Key technologies of the "Feitian" extravehicular space suit in ensuring the safety of astronauts' lives

On July 4, 2021, astronauts Liu Boming and Tang Hongbo successfully exited the spacecraft and showed the world China's independently developed new generation of "Feitian" extravehicular space suits. The key technologies of the new generation of "Feitian" extravehicular space suits to ensure the safety of astronauts played an important role in this flight mission.

The "Feitian" extravehicular space suit is a key equipment to ensure the safety of astronauts in the harsh environment of space. Its technology is complex and is equivalent to a miniature manned spacecraft. It is an important manifestation of a country's manned spaceflight capabilities.

It consists of clothing, helmets, gloves and space boots. The innermost layer of the clothing is the lining and urine collection device. Outside the lining is a liquid-cooled ventilation layer for heat dissipation. Further out is a pressurized airtight layer to generate a certain pressure. Then there is a restriction layer to prevent outward expansion. Outside the restriction layer is an insulation layer to cope with large temperature changes. The outermost layer is a protective layer with multiple functions.

As for the helmet of the "Feitian" extravehicular space suit, it has an extremely wide field of vision. Its face window has as many as 4 layers, two of which are filled with high-purity nitrogen to prevent fogging. The outer layer of the face window is a protective mirror, and the outermost layer is a movable gold-plated filter. When astronauts work facing the sun, they can pull it down to prevent the light from directly shining into their eyes.

Schematic diagram of the helmet of the new generation of "Feitian" extravehicular space suit

The outer layer of its gloves is made of fiber fabric, and there are two airtight layers made of special heat-insulating rubber, which can withstand high temperatures up to 100°C, but the fingertips of the gloves have only one airtight layer to allow astronauts to maintain their sense of touch. The boots are composed of pressure boots and extravehicular thermal protection boots to ensure that the astronauts' feet are adequately protected.

The control panel of Feitian is located on the front chest, which is used to operate various devices and is the location of its "brain". Since it is difficult for astronauts to see the switches on their chests after putting on their space suits, Feitian has a small mirror on its left wrist to allow astronauts to observe with the help of the mirror image.

In addition, there is a portable life support system on the back of the space suit to provide oxygen and other conditions necessary to sustain life. When the space walk time is long, it is also equipped with a water bag and a long hole for placing food bars.

The "Feitian" extravehicular suit used by my country's space station is one of the most advanced space suits in the world, which is inseparable from the joint efforts of aerospace workers. Now that the aerospace industry has developed to the stage of lunar exploration, in order to cope with the complex environment of the moon, the research and development team has designed and developed a new space suit - the lunar suit.

Lunar suit: Born for exploring the moon

China's lunar suit debuts

On September 28, 2024, the lunar suit was unveiled in China for the first time. The lunar suit is developed and designed based on the extravehicular space suit. Compared with the extravehicular space suit, the lunar suit has a more prominent overall structure, and the external equipment components are miniaturized and integrated, making it more like a real "clothes". It inherits many advanced technologies and design concepts of the extravehicular space suit, and at the same time has made a series of innovations and improvements to the special environment on the lunar surface.

The lunar environment is extremely harsh, with a huge temperature difference between day and night on the surface. The temperature can reach 127°C during the day and drop to -183°C at night. The lunar suit uses highly efficient heat insulation and thermal insulation materials to ensure the safety of astronauts in extreme temperatures. These materials usually have a multi-layer structure, including a reflective layer, a heat insulation layer, and a thermal insulation layer. In order to further adapt to the temperature changes on the lunar surface, the lunar suit is also equipped with an advanced temperature regulation system. This system can automatically adjust the temperature inside the space suit according to the astronaut's physical condition and the temperature changes of the external environment. The temperature regulation system usually includes heating elements, cooling elements, and temperature sensors.

The lunar surface is not protected by the atmosphere and is directly exposed to cosmic rays and solar radiation. Therefore, the structural design of the lunar suit also takes into account the requirements of radiation protection. For example, the face shield of the lunar suit adopts a panoramic anti-glare window, which can minimize the incident angle of radiation and improve the radiation protection effect.

The moon's surface is covered with dust, which is very fine and has a certain degree of adhesion. In order to prevent dust from entering the space suit and causing harm to the astronauts, the outer layer and mask of the lunar suit are made of wear-resistant and anti-adhesion materials, which can effectively block the adhesion of dust. At the same time, the joints and seals of the lunar suit are also specially designed to prevent the entry of dust.

Improved lunar suit joint configuration

In addition, the lunar suit can support astronauts to carry out activities on the lunar surface for a long time, which is inseparable from its unique functional characteristics. The lunar suit provides astronauts with necessary oxygen, regulates temperature, removes carbon dioxide, and effectively protects the safety of astronauts through its life support system. At the same time, it can maintain appropriate internal pressure through pressure protection to prevent the vacuum environment from causing harm to astronauts. In addition, the communication system allows astronauts to maintain smooth communication with the ground control center, and the energy supply provides continuous power support for equipment and systems. Because of this, astronauts can move on the lunar surface for a long time.

In the future, China's space program will continue to improve the design and technological innovation of the Feitian extravehicular spacesuit and lunar suit, allowing them to make greater contributions to space station construction and lunar exploration, and provide strong support for human exploration of space.

Some of the information comes from CCTV.com, Science Popularization China, and Guangming Online.

(Scientific review: Li Liang, member of the Science Popularization and Education Committee of the Chinese Space Society)