Medical problems that could put an end to deep space exploration

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

If so, then we suggest that you familiarize yourself with a selection of the 20 most likely health problems that the pioneers of the era of human space colonization will have to face (if we do not solve them before this moment).

Problems with heart

Western medical research and observation of 12 astronauts showed that with prolonged exposure to microgravity, the human heart becomes spherical by 9.4 percent stronger, which in turn can cause a variety of problems with its work. This problem can become especially urgent during long space travels, for example, to Mars.

“The heart works in space in a different way than it does in Earth's gravity, which in turn can lead to the loss of its muscle mass,” says Dr. James Thomas of NASA.

"All of this will have serious consequences after returning to Earth, so we are currently looking for possible ways to avoid or at least reduce this loss of muscle mass."

Experts note that after returning to Earth, the heart regains its original shape, but no one knows how one of the most important organs of our body will behave after long flights. Doctors are already aware of cases when returning astronauts experienced dizziness and disorientation. In some cases, there is a sharp change in blood pressure (there is a sharp decrease), especially when a person is trying to stand up. In addition, some astronauts experience arrhythmias (abnormal heart rhythms) during missions.

The researchers note the need to develop methods and rules that will allow deep space travelers to avoid these types of problems. As noted, such methods and rules could be useful not only for astronauts, but also for ordinary people on Earth - those experiencing heart problems, as well as those who are prescribed bed rest.

At the moment, a five-year research program has begun, the task of which will be to determine the level of the impact of space on the acceleration of the development of atherosclerosis (a disease of the blood vessels) in astronauts.

Drunkenness and mental disorders

Although an anonymous survey conducted by NASA cleared suspicions of frequent alcohol consumption by astronauts, in 2007 there were two cases in which virtually drunk NASA astronauts were allowed to fly inside the Russian Soyuz spacecraft. At the same time, people were allowed to fly even after the doctors who were preparing these astronauts for the flight, as well as other members of the mission, told their superiors about the very hot condition of their colleagues.

According to the security policy of the time, NASA spoke of an official ban on alcohol consumption by astronauts 12 hours before training flights. The operation of this rule was also tacitly assumed for the duration of space flights. However, after the above incident, NASA was outraged by such carelessness of astronauts that the agency decided to make this rule regarding space travel official.

Former astronaut Mike Mallane once said that astronauts consumed alcohol before the flight to dehydrate the body (alcohol dehydrates) in order to ultimately reduce the load on the bladder and suddenly not want to use the toilet at the time of launch.

The psychological aspect also had its place among the dangers in space missions. During the Skylab 4 space mission, astronauts were so "tired" of communicating with the space flight control center that they turned off radio communications for almost a day and ignored messages from NASA. In the aftermath of this incident, scientists are trying to identify and address potential negative psychological effects that could arise from more stressful and lengthy missions to Mars.

Lack of sleep and the use of sleeping pills

A ten-year study has shown that astronauts are clearly not getting enough sleep in the last weeks before launch and during the start of space missions. Among those surveyed, three out of four admitted that they used medications that helped them fall asleep, even though the use of such medications could be dangerous while flying the spacecraft and when working with other equipment. The most dangerous situation in this case could be when the astronauts were taking the same medicine at the same time. In this case, at the time of an emergency that requires an urgent solution, they could just oversleep it.

Despite the fact that NASA assigned each astronaut to sleep at least eight and a half hours a day, most of them took only about six hours of rest each day during missions. The severity of this load on the body was compounded by the fact that during the last three months of training before the flight, people slept less than six and a half hours daily.

"Future missions to the Moon, Mars and beyond will require more effective measures to address sleep deprivation and optimize human performance in space flight," said senior researcher Dr. Charles Kzeiler.

“These measures could include changes to the work schedule, which will be carried out taking into account the exposure of a person to certain light waves, as well as changes in the behavioral strategy of the crew to more comfortably enter the state of sleep, which is imperative to restore health, strength and good mood the next day..

Loss of hearing

Research has shown that since the days of space shuttle missions, some astronauts have experienced temporary significant and less significant hearing loss. They were noted most often when people were exposed to high sound frequencies. The crew members of the Soviet space station Salyut-7 and the Russian Mira also had minor or very significant hearing loss effects after returning to Earth. Again, in all these cases, the cause of partial or complete temporary hearing loss was exposure to high sound frequencies.

The crew of the International Space Station is required to wear earplugs every day. To reduce noise aboard the ISS, among other measures, it was proposed to use special sound-insulating gaskets inside the walls of the station, as well as the installation of quieter fans.

However, in addition to the noisy background, other factors can also affect hearing loss: for example, the state of the atmosphere inside the station, increased intracranial pressure, and increased levels of carbon dioxide inside the station.

In 2015, NASA plans, with the help of the ISS crew, to begin exploring possible ways to avoid the effects of hearing loss during one-year missions. Scientists want to see how long these effects can be avoided and find out the acceptable risk associated with hearing loss. The key task of the experiment will be to determine how to minimize hearing loss completely, and not just during a specific space mission.

Stones in the kidneys

One in ten people on Earth sooner or later develop a kidney stone problem. However, this question becomes much more acute when it comes to astronauts, because in space, the bones of the body begin to lose useful substances even faster than on Earth. Salts (calcium phosphate) are secreted inside the body, which penetrate the bloodstream and accumulate in the kidneys. These salts can be compacted and take the form of stones. At the same time, the size of these stones can vary from microscopic to quite serious - up to the size of a walnut. The problem is that these stones can block blood vessels and other flows that feed the organ or remove excess substances from the kidneys.

For astronauts, the risk of developing kidney stones is more dangerous because under microgravity conditions, the volume of blood inside the body can decrease. In addition, many astronauts do not drink 2 liters of fluids a day, which, in turn, could provide complete hydration of their body and prevent stones from stagnating in the kidneys, removing their particles along with urine.

It is noted that at least 14 American astronauts developed a problem with kidney stones almost immediately after the completion of their space missions. In 1982, a case of acute pain was recorded in a crew member aboard the Soviet Salyut-7 station. The astronaut suffered from severe pain for two days, while his companion had no choice but to helplessly watch the suffering of his colleague. At first, everyone thought of acute appendicitis, but after a while a small kidney stone came out with the cosmonaut's urine.

Scientists have been developing a special ultrasound machine the size of a desktop computer for a very long time, which can detect kidney stones and remove them using pulses of sound waves. It seems that on board the ship next to Mars, such a thing could definitely come in handy …

Lung disease

Despite the fact that we do not yet know with certainty what negative health effects can be caused by dust from other planets or asteroids, scientists are still aware of some very unpleasant consequences that can manifest themselves as a result of exposure to moon dust.

The most serious effect of dust inhalation is likely to be on the lungs. However, incredibly sharp particles of moon dust can cause serious damage not only to the lungs, but also to the heart, at the same time causing a whole bunch of various ailments, ranging from severe organ inflammation and ending with cancer. For example, asbestos can cause similar effects.

Sharp dust particles can harm not only internal organs, but also cause inflammation and abrasions on the skin. For protection, it is necessary to use special multi-layer Kevlar-like materials. Moon dust can easily damage the corneas of the eyes, which in turn can be the most serious emergency for humans in space.

Scientists regret to note that they are unable to model the lunar soil and carry out the full set of tests necessary to determine the effects of lunar dust on the body. One of the difficulties in solving this problem is that on Earth, dust particles are not in a vacuum and are not constantly exposed to radiation. Only additional studies of dust directly on the surface of the Moon itself, and not in the laboratory, can provide scientists with the necessary data to develop effective methods of protection against these tiny toxic killers.

Failure of the immune system

Our immune system changes and responds to any, even the smallest, changes in our body. Lack of sleep, inadequate intake of nutrients, or even normal stress can all weaken our immune system. But this is on Earth. A change in the immune system in space can eventually turn into a common cold or carry a potential danger in the development of much more serious diseases.

In space, the distribution of immune cells in the body does not change much. A far greater threat to health can be caused by changes in the functioning of these cells. When the functioning of the cell decreases, the already suppressed viruses in the human body can be reawakened. And to do this virtually secretly, without the manifestation of symptoms of the disease. When immune cells become more active, the immune system overreacts to stimuli, causing allergic reactions and other side effects such as skin rashes.

"Things like radiation, germs, stress, microgravity, sleep disturbance and even isolation can all affect the way the immune systems of the crew members work," says NASA immunologist Brian Krushin.

"Long-term space missions will increase the risk of infections, hypersensitivity, and autoimmune problems in astronauts."

To solve problems with the immune system, NASA plans to use new methods of anti-radiation protection, a new approach to balanced nutrition and medicine.

Radiation threats

The current very unusual and very prolonged lack of solar activity could contribute to dangerous changes in the level of radiation in space. Nothing like this has happened for almost the past 100 years.

“While such events are not necessarily a stopping factor for long missions to the Moon, asteroids, or even Mars, galactic cosmic radiation itself is a factor that can limit the planned timing of these missions,” says Nathan Schwadron of the Institute. terrestrial, oceanic and space exploration.

The consequences of this kind of exposure can be very different, ranging from radiation sickness and ending with the development of cancer or damage to internal organs. In addition, dangerous levels of background radiation reduce the effectiveness of the spacecraft's anti-radiation protection by about 20 percent.

In just one mission to Mars, an astronaut can be exposed to 2/3 of the safe dose of radiation that a person can be exposed to in the worst case during his entire life. This radiation can cause changes in DNA and increase the risk of cancer.

“When it comes to cumulative dose, it’s the same as doing a full CT scan of the body every 5-6 days,” says scientist Carey Zeitlin.

Cognitive problems

In simulating the state of being in space, scientists have found that exposure to highly charged particles, even in small doses, makes laboratory rats respond to their surroundings much more slowly, and in doing so, the rodents become more irritable. Observation of the rats also showed a change in the composition of the protein in their brains.

However, scientists are quick to note that not all rats showed the same effects. If this rule holds true for astronauts, then, according to the researchers, they could identify a biological marker that indicates and predicts the early manifestation of these effects in astronauts. Perhaps this marker would even allow finding a way to reduce the negative effects of radiation exposure.

Alzheimer's disease is a more serious problem.

"Exposure to radiation levels equivalent to that experienced by humans on a flight to Mars can contribute to the development of cognitive problems and accelerate the changes in brain function that are most often associated with Alzheimer's disease," says neurologist Kerry O'Banion.

"The longer you are in space, the greater the risk of developing the disease."

One of the comforting facts is that scientists have already managed to investigate one of the most unfortunate scenarios of exposure to radiation. They exposed laboratory mice at one time to a level of radiation that would be characteristic of the entire time on a mission to Mars. In turn, people flying to Mars will be exposed to radiation in a metered dose, during the three years of the flight. Scientists believe that the human body can adapt to such small doses.

In addition, it is noted that plastics and lightweight materials can provide people with more effective radiation protection than currently used aluminum.

Loss of sight

Some astronauts develop severe vision problems after being in space. The longer the space mission lasts, the more likely the chance of such dire consequences.

Among at least 300 American astronauts who have undergone medical screening since 1989, 29 percent of people who have been in space on two-week space missions and 60 percent of people who have worked aboard the International Space Station for several months have had vision problems. …

Doctors from the University of Texas performed brain scans of 27 astronauts who had been in space for more than a month. In 25 percent of them, a decrease in the volume of the anteroposterior axis of one or two eyeballs was observed. This change leads to farsightedness. Again, it was noted that the longer a person is in space, the more likely this change is.

Scientists believe that this negative effect can be explained by the rise of fluid to the head in conditions of migrogravity. In this case, cerebrospinal fluid begins to accumulate in the cranium, and intracranial pressure rises. Liquid cannot seep through the bone, therefore, it begins to create pressure on the inside of the eyes. Researchers are not yet sure if this effect will diminish in astronauts arriving in space for more than six months. However, it is quite obvious that it will be necessary to find out before the moment people are sent to Mars.

If the problem is caused solely by intracranial pressure, then one of the possible solutions would be to create conditions of artificial gravity, every day for eight hours, while the astronauts sleep. However, it is too early to say whether this method will help or not.

"This problem needs to be addressed, because otherwise it may turn out to be the main reason for the impossibility of long space travel," says scientist Mark Shelhamer.

Zero gravity kills the brain

Long stay in space in zero gravity can cause serious changes in the brain, Siberian scientists have found out by examining the state of mice that have been in orbit.

The results will make it possible to create systems for preventing and correcting the negative impact of weightlessness on the astronauts' organism. The most interesting of the data obtained concerns the dopamine system. We saw that the expression of its key genes decreases after a month in orbit. This suggests that the dopamine system of the brain, which is normally responsible for fine coordination of actions, and in general - for the control of movements, degrades.

In the long term, such a change can lead to the development of a parkinson-like state. Because if your expression of an enzyme that synthesizes dopamine decreases, then the level of the neurotransmitter itself also decreases, and, ultimately, a motor deficit develops, "- quotes the words of a researcher at the Laboratory of Neurogenomics of Behavior at the Federal Research Center Institute of Cytology and Genetics SB RAS, Anton Tsybko, official publication SB RAS "Science in Siberia" See also Launch of the Soyuz TMA-17M manned transport vehicle.

In addition, the scientist noted changes in another extremely important brain structure - the hypothalamus. Here, signs of apoptosis (programmed cellular "suicide") were found, which is most likely provoked by microgravity. It has already been confirmed: both in orbit and on Earth - in experiments simulating the state of weightlessness - apoptosis of neurons increases. "This is fraught with a general deterioration of metabolism and much more. Considering that in zero gravity the body is already under attack, any change in its functioning for the worse can have quite serious consequences," Tsybko explained.

Scientists noted that, fortunately, these changes are not fatal, and physical activity completely prevents them from occurring. In animals, physical activity is restored within a week. The brain begins to accumulate lost time again, the level of serotonin, dopamine returns to normal quite quickly. Within a month, neurodegeneration does not have time to occur.

To launch mice into space for a longer time still seems problematic. Physical education is a rescue for cosmonauts The study was carried out on laboratory mice that made a 30-day space journey on the Bion-M1 biosatellite. Scientists note that the anatomy and physiology of mice are in many ways similar to humans, our genomes coincide by 99%, so linear mice are the most suitable objects for studying the mechanisms of adaptation to weightlessness. However, there is a significant difference: astronauts, unlike mice, are able to consciously force themselves to move, they exercise more than four hours a day, which means they stimulate the motor centers in the brain and minimize the risk of damage to the dopamine system.

However, if you stay in orbit for at least two weeks and do not perform any special physical exercises, then upon returning to Earth the condition turns out to be very difficult and a long rehabilitation is required. Bion is a series of Soviet and Russian spacecraft developed by TsSKB-Progress and intended for biological research. For 11 flights, experiments were carried out on them with 212 rats, 12 monkeys and a number of other animals. The Bion-M1 satellite was launched on April 19, 2013 and returned to Earth a month later.

In addition to mice, there were Mongolian gerbils, gecko lizards, fish, freshwater and grape snails, carpenter beetle larvae, microorganisms, algae, lichens and some higher plants on board. To date, the Bion-M1 experiment has been completed. Bion-M2 is to be launched in the coming years.