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by Viktoria Kabatne Urban

The European Space Agency recently recruited astronauts where almost anyone with a master’s degree in any STEM subject area could apply regardless of age, pilot training, gender, religion, disability, and sexual orientation. The monthly salary was promised to be between €5400 - 8600 (£4,669 - 7,435) depending on experience, not to mention the benefits. Sounds like a good job? What conditions had to be met and what challenges awaited the applicants? Can a space trip have any disadvantages?


The six-step application process consisted of:

1. Screening process based on the documents submitted during the application

2. Cognitive, technical, motor coordination and personality tests

3. Psychometric testing, individual and group tasks, practical exams

4. Medical examinations to assess physical and mental condition

5. Commission interview, during which technical and behavioural competencies were examined

6. Final interview with the CEO of ESA and then decision making.


The six-step application process included an 80-page health requirement list and the examinations were to be self-funded by the applicant - although organizations were set up to offer financial support so that monetary difficulties did not pose a problem for someone otherwise absolutely deserving of a space in space.


The tests included, among others, psychological tests where they examined what their individual goals were, how important the goals of the team were to the individual, what leadership and teamwork skills they had. They were also tested for stress tolerance and were subjected to strenuous physical exercise: tilting table test, checking of the lungs, heart and circulatory system, and swimming (in case they landed in water on their return). The real exertion for any astronaut, however, only begins after selection. Each astronaut receives pre-launch quarantine and medical training - as the flight surgeon (space doctor) may be in need of medical care - and they are then instructed to perform their individual duties, spacewalks, and receive Russian language training as well. Almost every element of this education takes place underwater, so that astronauts get used to having to move and behave differently, not taking their protective gear off, etc., but unfortunately this does not provide grounds for 100% adequate microgravity training because the conditions are not the same as in space. For those who successfully pass the training, the first difficulty begins in the hours before launch, when they have to sit and wait in an almost lying position, knees up and wait for all the checks and preparations to be done outside.

The fluids in the body then flow back from the feet to the torso, which fluids will soon want to leave the body. This is obviously not possible in the hours before launch, so astronauts wear a kind of a “diaper” officially called a “maximum absorbency garment” or MAG for short and yes, it really does what a diaper does, because if you have to go, you have to go.

The other surprises that hit the astronauts in space which they try to prepare for as best they can here on Earth are:


1. Vestibular system: nausea that is worth alleviating, as astronauts wearing a full protective gear may drown in the stomach contents entering the helmet; space adaptation syndrome lasts for about three days, during which time any sudden head movement is contraindicated. Due to microgravity, a phenomenon called ocotonia occurs in the ear, which means that the astronaut does not know which way is up and the body thinks it has been poisoned, which can lead to nausea and vomiting against which, of course, they get medication prior to launch. Research is currently looking at the impact of this phenomenon on hearing-impaired people, as their ears work a little differently.


2. Cardiovascular system: in the first 24-72 hours blood pressure increases, the morphology of the heart changes, more blood pushes into the head causing the face to swell up and the legs to become thinner (“puffy face and chicken legs” syndrome). This adjusts over time to midpoint of pre-flight standing and supine blood pressure. This difference in blood pressure is the reason for when astronauts return to Earth, they cannot stay standing for long (orthostatic intolerance) because when they land, the opposite happens: blood flows into the legs, so the brain does not get enough blood to stand for long periods. For reasons that are still unknown, the number of red blood cells falls in space as well which causes astronauts to develop anaemia.


3. Decompression sickness: there is increased release of nitrogen from the body’s tissues due to the decreased pressure causing joint and muscle pain, fatigue, confusion. Attempts are made to prevent or alleviate this by inhaling pure oxygen before launch.


4. Vision: the changed pressure affects intracranial pressure, which flattens the back wall of the eyeball (globe flattening). Hypermetropia (farsightedness) develops as a result of which astronauts will need reading glasses. This problem affects 1/3 of astronauts in the short term and 2/3 in the long term, but there is no data yet on what happens to the eye or the intracranial pressure after more than 12 months which would be worthwhile to examine prior to manned Mars expeditions, as these may jeopardize the mission. Efforts are currently being made to develop non-invasive methods applicable in space for measuring, monitoring and treating intracranial pressure. Researchers have concluded that a certain diabetes medication could alleviate these symptoms, but no long-term solution has been found yet.


5. Bones and muscles: an accelerated aging process takes place in space due to microgravity: there is a breakdown of bone and muscle mass, which mainly affects those responsible for posture, as well as the lower limbs. To prevent muscle breakdown, astronauts need to train for several hours every day under special conditions, like being tied down with cords to mimic Earth’s gravity. The risk of kidney stones also increases because there is an increased breakdown of calcium in the bones which cannot be incorporated elsewhere, so it is deposited in the kidneys.

6. Digestive and endocrine system: taste perception changes. Metabolism accelerates, the body needs more energy in space which escalates even more with space walks. Astronauts tend to crave carb-rich foods much more, yet they return to planet Earth slimmer. Due to the effects of physiological stress, hormonal changes occur: the increased circulation of corticosteroids and catecholamine’s leads to immune dysregulation. As a result, anyone who has had a problem with herpes virus is more likely to get cold sores and someone who has not had any allergies until then may even become allergic to certain foods in space, for example. That is why Michelin star chefs need to prepare astronauts’ food in a special way so that they don’t contain any allergens.


7. Sleep Disorder: depending on where the astronauts are in space, they may see more sunrises than we do here on Earth, so sleep disturbances occur due to light. Astronauts also need to get used to sleeping strapped down because of microgravity.

8. Cosmic radiation: each year spent in space increases the risk of cancer by 10 %. This is especially dangerous for women as they are more prone to diseases of this nature even under normal Earth conditions.


9. On return: very strong nausea can be expected again due to the reversal of the aforementioned phenomena. All astronauts are inspected immediately upon arrival and then everyone is transported back to their training site. If emergency arises on the way, there is usually a standby hospital halfway where astronauts can receive emergency care before they are transported further; those trained in the USA receive such care in a dedicated hospital in Scotland. Once the astronauts have “arrived home”, they undergo further health examinations. Due to the orthostatic intolerance, we can see them in a wheelchair in the moments after returning. They need physiotherapy and a progressive exercise regime to regain their lost muscle mass, and while this also has a positive effect on bone mass, research shows that they can never regain lost bone mass, especially that of tubular bones. As astronauts lose weight during their journey in space, they need a nutritionist as well to regain their original weight and to deal with any allergies they may have developed. It is recommended to wait a year between two space missions, as the various systems in the body need to return to their original, healthy state and that takes at least six months for most of them.

If all this was not enough strain on the body during a space trip, there could even be an emergency: dental problems, appendicitis, acute surgical issues, trauma, heart attack, increased intracranial pressure, and so on. The much-needed space medicine faces the following difficulties in the case of emergencies:


1. The shelf life of drugs: is not the same in space as on Earth due to the different conditions. This varies from product to product, there is no general rule for it, but the raw materials decompose faster due to microgravity and increased radiation.


2. Liquids behave differently in space: so getting them out with a syringe, for example, is difficult. The liquid is pushed to the two opposing edges of the container due to the change in gravity and an air bubble is formed in the middle. Getting the air bubble into the syringe and then injecting it into the patient's bloodstream can be fatal, so the procedure must be performed using a special technique.

3. Telemedicine: where diseases are diagnosed remotely (from Earth) using telecommunication devices, has serious limitations at the moment but, ultrasound examinations are regularly performed this way.

4. Surgery in space: space is an unstable place due to the lack of gravity. For surgery to occur in space the person to be operated on must be strapped down and the person performing the operation must be propped up as well as organs may float out of the body during the operation. The devices also need to be stabilized and anaesthesia does not work in the same way as on Earth conditions either. Wound healing is different as well, which must also be taken into account. (Remember the flatworms: if we cut off its tail on Earth, it will grow back but in space, one in fifteen will not grow a tail back, but grow a second head).

5. Resuscitation: the person to be revived must be restrained & the person performing CPR must also be stabilized. The most effective method for this is the hand-stand method, where the resuscitator puts his foot on the ceiling and revives with his hands. So far, this is the most stable method, but the astronaut performing the resuscitation must be tall enough to be able to do this. The second in the order of efficiency is the Evetts-Russomano method, where the resuscitating astronaut wraps their legs over the torso of the person, and while floating back and forth in the space cabin, performs the needed procedure. The least effective method is the reverse bear hug, where the resuscitator hugs the patient from behind. They will both float around this way as well but unfortunately this method makes ventilation very difficult. In the case of all three methods, it is important where the astronauts are: on the International Space Station, the Moon, Mars, etc. as due to different gravitational values, their body weight, which contributes to the force they exert during manual resuscitation changes. If they are 70 kg on Earth, that is 26.3 kg on Mars and 11.6 kg on the Moon. In the context of CPR, the question also arises as to whether it is ethical to revive someone if they cannot be given appropriate medical treatment afterwards.

6. Life, limb, mission paradigm: while the Soyuz reaches the International Space Station in a few hours, the same journey to the Moon takes three days but when it comes to Mars, we have to talk about months, plus an 8-56-minute time lag for getting the information from there. According to this paradigm, they may have to sacrifice someone’s eye, or a limb for the mission’s success, as there may not be any other options, expertise, or just the right tools for treatment, and there may be obstacles to getting home as well. It is still a matter of debate whether to remove for example the appendix or the gallbladder of the astronauts before manned Mars expeditions in order to prevent probable emergencies. The other problem is getting the drugs into space, possibly to Mars, as this is not a cheap or easy task, and since they break down sooner in a microgravity environment, they may become unusable by the time they reach their destination.

ESA offered a fantastic opportunity for a huge amount of people to ascend into space without having to pay millions and even be able to help humanity with their work. The journey however is never safe & it is also worth preparing for permanent damage to the body, as no matter how advanced space medicine is at present, it is always facing more and more difficulties. In light of all this, anyone who wants to apply to be an astronaut in the future should keep an eye on ESA, NASA and SpaceX missions.

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