Breaking news: Spacewalks on the International Space Station were completely halted. The reason was that the space suit helmet was leaking?

According to media reports, on August 5, an astronaut on the International Space Station had water suddenly enter his helmet while performing a mission outside the cabin. For safety reasons, NASA (National Aeronautics and Space Administration) called off all spacewalk missions on the International Space Station.

For some time, it seems that China always has good things happening, with good news about the space station coming one after another; while foreigners always have bad luck but it rains all night, and the International Space Station is also full of loopholes. One moment the cabin is leaking, the next moment Russia is threatening to break up, and now there is a leak in the helmet.

Is it true that "the enemy is getting worse and worse, and we are getting better and better"? It seems that we will really lead the world soon, haha. Many netizens cheered excitedly, and the mood became more and more excited. But I won't join in the fun today, and talk about the problem of why space suit helmets leak from a scientific perspective.

Why does the space suit helmet leak? Where does the water come from?

The complexity of the space suit is beyond the imagination of most people. Its functions include: protecting astronauts from decompression, radiation, vacuum, low temperature or high temperature in space; providing air for astronauts to breathe and life support systems such as eating, drinking, defecating and urinating during their extravehicular work. Therefore, the space suit is actually a small spaceship with extremely high technological content and high cost.

So, if the space suit is expensive, why does it leak? We know that there is no water in the high vacuum of space, so where does the water come from?

Here we need to clarify a misunderstanding. The so-called water leakage is definitely not a gap in the helmet, leaking in from space. If there is a gap in the helmet, it is not a problem of water leakage, but a problem of air leakage and decompression, and the astronauts will die quickly. Therefore, this so-called water leakage is still a problem inside the space suit.

In fact, this kind of accident has occurred not once or twice, but many times. To sum up, there are two main reasons: first, condensation accumulates in the helmet due to equipment failure, which makes it impossible to remove the water vapor breathed by astronauts in time; second, the cooling water circulation system pipeline ruptures, causing cooling water to leak into the helmet.

The latter is more dangerous in terms of consequences, because if the cooling water leaks a large amount and is not handled in time, it will submerge the helmet and suffocate the astronauts. However, the accumulation of condensed water cannot be ignored, because when too many water droplets gather, they will form water beads, which will float in the helmet in the weightless state of space. If the astronauts inhale them, they will cause choking or even suffocation.

Moreover, excessive accumulation of condensed water will cause the temperature control system of the space suit to malfunction. When the temperature in space is over 100 degrees below zero or over 100 degrees under the sun, the failure of the temperature control system is very dangerous.

Typical helmet leakage accidents include:

In July 2013, during an extravehicular activity on the International Space Station, Italian astronaut Parmitano's helmet was flooded with 1.5 liters of water, which flooded his mouth and caused difficulty breathing. In order to save his life, he had to end the spacewalk mission early and return to the capsule. This accident still scares Parmitano.

There were two helmet leaks in 2015. One time, astronaut Virtz found water droplets floating in his helmet while walking in space. He thought it was not serious and insisted on completing the mission before returning to the spacecraft. According to relevant information, another astronaut's helmet leaked in the same year, and the water level was as high as his eyes, and he almost drowned. However, I did not find the name of this astronaut, so it is difficult to confirm the truth of the news.

This kind of accident happened again in March this year, when American astronaut Raja Charlie and German astronaut Matthias Maurer of the European Space Agency were performing an extravehicular mission. NASA was also broadcasting it live, but during the approximately 6.5-hour extravehicular activity, one of the astronauts' helmet leaked, but fortunately it was not serious, and he and his companions finally completed the mission before returning. NASA did not disclose which astronaut's helmet leaked.

This happened again on August 5. Although NASA did not disclose the cause of the leak, it seemed to be serious, so all spacewalks were suspended.

The reason for a series of space suit accidents is that these space suits are too old. The Seahawk extravehicular space suits used by Russian astronauts are specified to be used 12 times, after which they are thrown away and burned up in the atmosphere along with the abandoned cargo spacecraft. However, the fourth generation of extravehicular space suits used by the United States have been in use for more than 40 years!

The past and present of space suits/

The development of space suits has gone through four generations of upgrades. The first and second generations were very simple. They were worn by astronauts in low-orbit spacecraft in the late 1960s and early 1970s, at the beginning of human space flight, and they could not go out of the cabin. The third generation of space suits achieved a qualitative change, allowing astronauts to move outside the cabin, and realized the Apollo manned lunar landing and activities on the moon.

The third-generation space suit can not only withstand the moon's high vacuum and low pressure, high temperature of 127 degrees and low temperature of minus 183 degrees, cosmic rays and high-intensity electromagnetic radiation, but also withstand the bombardment of micrometeorites.

The development of each generation of space suits in the United States has cost a huge amount of money, more than $1 billion. For example, the fourth generation of space suits, which began to be developed in 1974, were mainly used for extravehicular missions. The final product of this space suit was 18 sets, and the cost of each set reached $15 million to $22 million at the time, which is equivalent to $124 million per set at the current price.

The fourth generation of the US space suit has been greatly improved on the third generation. It weighs only 60 kilograms and can be put on in 10-15 minutes. The life support system used can allow astronauts to work for up to 7 hours, and it can resist more cosmic substances, such as high-energy particles and small meteorites. At the same time, more water and food can be stored in the helmet of the space suit.

Of the 18 space suits, two were damaged during testing, four were destroyed in space shuttle accidents, and one was destroyed in the explosion of a Falcon 9 rocket. The remaining 11 were used for more than 40 years.

In the vacuum environment of space, the temperature on the sun-facing side can reach 121 degrees Celsius, while the temperature on the shady side can drop to -157 degrees Celsius. Adding to the damage caused by radiation, only 4 sets are still usable. A few days ago, another set leaked, and it seems that only 3 sets are usable.

So far, humans have performed more than 440 spacewalks, and these 11 spacesuits have been used for at least 200 of them, which is a great achievement. So why can't they replace the spacesuits? It's easier said than done.

In fact, the United States has been developing new space suits since 2008. As of 2021, the research and development costs have already reached $420 million. It is said that another $625 million will be needed to complete the project, which is more than $1 billion! After the project is completed, two sets of finished products can be provided. It can be seen that the cost of one set of this new space suit is as high as $500 million.

In 2019, NASA once showed off a space suit that looked very flexible. NASA claimed that it was a new space suit, Xemu, which could provide life support for 6 days of extravehicular activities and was prepared for the Artemis moon landing mission. But at the same time, NASA said that the finished product of this space suit could not be produced before April 2005, which affected the time of returning to the moon.

On June 1 this year, NASA announced that due to major delays in the Xemu spacesuit, it plans to pay $3.5 billion in research and development fees to two other companies to develop new spacesuits. It seems that they are starting from scratch, and the research and development costs are staggering. Are they going to develop spacesuits for landing on Mars?

This is undoubtedly the fifth generation of space suits, but it also shows from one side that these space suits cannot adapt to extravehicular missions on the International Space Station.

NASA hopes that the service life of those outdated fourth-generation space suits can be extended to 2028, and they will coexist with the International Space Station. It seems that American astronauts will have to continue to endure the problems of these space suits, and there may be more helmet leaks, but hopefully no casualties will occur.

According to relevant sources, the cost of China's space suit is only 30 million RMB, which is only 4.5 million USD. It is very advanced and easy to use. It is said that it only takes 5 minutes to put on. It is cheap and good quality. However, it is not known whether this cost includes the entire R&D cost.

Further reading: Introduction to space suits/

A space suit, also known as a space suit, is protective clothing worn by astronauts to ensure their life safety when performing missions in space, including indoor and extravehicular space suits.

The protection level of the space suit inside the cabin is lower than that outside the cabin. It is worn during the spacecraft's preparation for launch, ascent, return, orbit change, and rendezvous and docking phases to prevent accidents, so as to prevent pressure accidents. The extravehicular space suit is personal protective equipment used by astronauts during extravehicular activities.

The main thing to explain here is the extravehicular space suit. As we know, astronauts are exposed to the harsh environment of space when performing missions outside the cabin. They have to withstand high vacuum, low air pressure, high or low temperatures, high radiation and other space environments. Sometimes they perform missions outside the cabin for seven or eight hours.

Generally speaking, a space suit consists of three major parts: a protective part that has functions such as resistance to vacuum, pressure, radiation, isolation from high and low temperatures, and strict sealing; a life support system part; and a good communication system part.

The life support system includes: providing breathable oxygen (air), equipping enough drinking water and special food, so that astronauts can eat and drink as long as they open their mouths; the space suit can also process sweat and urine, allowing astronauts to move more comfortably and flexibly in the space suit, so as to complete complex extravehicular missions.

Quote: Introduction to China's space suit:

Weight: 120 kg

Main color: white

Cost: About RMB 30 million

Composition: The materials are a combination of soft and hard. From top to bottom, they are helmet, upper limbs, torso, lower limbs, pressure gloves, and boots.

Applicable: The limbs are equipped with adjustment straps, and by adjusting the length of the upper arm, forearm and lower limbs, people with a height of 1.60 meters to 1.80 meters can wear it.

Endurance: Can support 4 hours of extravehicular activity and can be reused 5 times

Upper limb joints: Clever use of bionic structure makes joint movements more flexible.

Wrist mirror: There is a small mirror installed on the wrist, through which astronauts can check various switches on their body at any time.

Backpack: 1.3 meters high, it is the sealed door for putting on and taking off the space suit (entry and exit). The life support equipment for the space suit is installed inside the backpack shell. The lower end of the backpack shell is equipped with a hanging bag, spare oxygen bottle, etc. The backpack is closed by tightening the steel cable and operating the closing handle.

Helmet: After scientific research, the field of view of the "Feitian" space suit helmet is wider than other similar products.

Camera: The helmet also has a camera that can record astronauts' extravehicular operations.

Lighting: There is a lighting on each side, which can illuminate the chest part of the suit, making it easier for astronauts to operate in the dark.

Alarm indicator light: There are alarm indicator lights on both sides. Once the clothing leaks, the alarm light will flash. There is also a language alarm.

Window: The window has 4 layers, 2 of which are pressurized structures. High-purity nitrogen is filled between the 2 layers to prevent fogging. The outside is a protective window, and the outer layer is a filter window with a low refractive index for sunlight. It can be pulled down facing the light.

Gloves: Tailor-made for each astronaut, they look particularly thick, a bit like boxing gloves.

Outer thermal protection gloves: The outer layer is fiber fabric, has two airtight layers, and uses special thermal insulation rubber material, which can withstand high temperatures up to 100°C; the fingertips have only one airtight layer to maintain the sense of touch; there are two layers of vacuum shielding insulation on the back of the fingers; there are convex rubber particles on the palm of the hand for anti-slip purpose; the gloves can hold objects as thick as a 25 mm pencil.

Heat protection cover: There is a foldable heat protection cover on the back of the hand to cover the fingers, improve the heat protection ability of this part and ensure the joint mobility of the fingers.

Watch: A specially designed space watch made of materials suitable for the special environment of spaceflight. It has a larger dial than ordinary watches and has more functions than ordinary watches. It has three small dials, namely hours, minutes and seconds; it can read Beijing time and flight time, and the dial can be turned to record time; Purpose: Space watches allow astronauts to clearly know the difference between day and night on Earth in the dark space, so as to ensure that the astronauts' daily routines are synchronized with the Earth and do not disrupt their biological clocks.

Clothing materials: Space suits must be vacuum-shielded and heat-insulated, and the fabrics used must combine multiple weaving methods to meet strength requirements.

Layers: The space suit has 6 layers: a comfort layer made of cotton cloth with special anti-static treatment, a backup airtight layer made of rubber, a main airtight layer made of a composite joint structure, a restriction layer made of polyester fabric, an insulation layer that achieves heat insulation through heat reflection, and the outermost outer protective layer. The torso has 7 layers, and the thickest one is the bag with 20 layers.

It is reported that the new generation of space suits developed by my country has retained its previous advantages, and has made great improvements in radiation protection, high and low temperature protection, high and low pressure protection, and unique life support systems. It can stay on "standby" outside the cabin for up to 8 hours, has added a urine collection device, can be worn by astronauts of 1.6 to 1.8 meters, realizes "unit digital scanning" technology, and has the ability to grasp objects as thick as a 25 mm pencil.

Judging from these indicators, it is better than the fourth-generation space suit of the United States. In short, the space suit is the life guarantee of astronauts in the extreme environment of space, and it is a tool to complete various complex tasks. It is the crystallization of the world's top technology and cannot be sloppy at all. What do you think about this? Welcome to discuss and comment.

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