Who has not ever thought about what the experience of traveling to space would be like? It is the dream of many and the privilege of only a few. However, getting there is not an easy path, as these lucky chosen ones work really hard to see their wish fulfilled.
Being an astronaut is a great responsibility, since not everyone is suitable for the position. In addition, training involves long hours of work and there is no guarantee that you will travel to space. However, many people compete to become NASA astronauts. More than 12,000 people have applied to join NASA’s 2021 class of astronauts. Do you know what the requirements to become an astronaut are? What they spend most of their time on? And how space travel affects the human body? Let’s find out.
What are the requirements to become an astronaut?
NASA has very strict requirements to be an astronaut. You must be in good physical shape and have sufficient technical skills to perform complex work on a spaceship. Additionally, you must have a master’s degree in engineering, physical science, life science, computer science, or math. It is also essential that you have three years of professional experience.
Candidates will have to pass a physical exam, although other skills such as diving, ease with languages (especially Russian) or survival training could be an advantage in the selection.
As of 2020, if you want to become NASA astronaut you must meet the following 4 qualifications:
- Be a U.S. citizen
- Possess a master’s degree in a STEM field
- Have at least two years of related professional experience obtained after degree completion OR at least 1,000 hours pilot-in-command time on jet aircraft.
- Be able to pass the NASA long-duration flight astronaut physical test.
What spacecrafts are like?
Astronauts use different spacecraft depending on the missions they are going to carry out. In the coming years NASA hopes to return to the Moon and Mars, so it is possible that they will use the Orion spacecraft to explore deep outer space.
This ship is equipped with electricity, propulsion, thermal control, air and water. In addition, the ship is made up of two modules (one of them manufactured in Europe) and weighs around 21 tons.
Also, the next NASA astronauts will be launched from US soil, something that has not happened for more than a decade.
What do astronauts spend most of their time on?
Although many think that astronauts are working in space most of the time, in reality they spend a great part of their careers on Earth. In fact, most of their time they are training or supporting other missions.
First, candidates must pass two years of basic training, where they learn survival training and technical skills. Upon completion, new astronauts can be sent on a space mission or assigned to technical duties in the Astronaut Office at The Johnson Space Center. There they are dedicated to advising NASA engineers on how to develop new spacecraft.
Why are there more men than women astronauts?
The reason is less obvious than you might expect, but equally decisive. The fact that there are fewer female astronauts is due to the fact that the threshold of exposure to space radiation for women is lower than that for men, so it is a health issue that limits the chances of seeing more female astronauts.
According to NASA, prolonged exposure to cosmic radiation, whether on the surface of some planets or in deep space, increases the chances of developing diseases such as cancer. If we take as an example a possible 1,000-day mission to Mars, the added risk of developing cancer in men would be between 1 and 19%; in women, this percentage is almost double. The reason why risk is greater for women is simple: they have organs that are sensitive to this disease, such as the ovaries and breasts. This fact makes it imperative to limit the space missions in which female astronauts can participate.
To alleviate this problem, the European Union launched a new project in January 2013, called Space Radiation Superconductive Shield (SR2S), which aims to solve the problem of exposure to space radiation for both female and male astronauts. The project aims to build a superconducting shield that will create a magnetic field around the spacecraft. This magnetic field will be 3,000 times stronger than that of planet Earth and will be able to deflect ionizing particles.
Among the organizations involved in SR2S are the National Institute of Nuclear Physics of Italy (INFN), CERN of Switzerland or the Commission for Atomic Energy and Alternative Energies of France (CEA).
What does an astronaut’s backpack contain?
In space, being a backpacker is a matter of survival.
A spacesuit is actually a small single-occupant craft, a pressurized environment capable of keeping the astronaut alive. That’s why it is so bulky and stiff – it has to maintain constant pressure inside.
The function of the large backpack is to house a life support system that regulates oxygen levels and eliminates the carbon dioxide that is generated when breathing. Known as the primary life support subsystem, this backpack contains the oxygen that astronauts breathe outside the spacecraft, and it also supplies electricity to the suit.
A fan keeps the oxygen circulating, and there is a tank that contains the cooled water that circulates through the spacesuit. It maintains body temperature in the cold environment of space.
The backpack can be supplemented with a device called Simplified Assistance Extravehicular Rescue (SAFER). This system has several small thrusters located in different areas. If an astronaut is separated from the International Space Station or his vehicle, he can use the SAFER to return.
How do astronauts protect themselves from cosmic radiation?
When astronauts circle the Earth aboard a space shuttle, they are at an altitude of between 300 and 500 kilometers. There, the ship’s thick aluminum shield neutralizes harmful cosmic radiation, that is, electrons and nuclei of atoms coming from all directions in space with a speed close to the speed of light.
Despite having this protection, space vehicles avoid crossing the so-called South Atlantic Anomaly (SAA) – an area of the Earth’s magnetic field in which exposure to cosmic rays is multiplied by 20. When rays are present in space during a solar flare, radiation amounts to a value a thousand times higher than usual.
During spacewalking astronauts face radiation, dust, debris, and extreme temperatures and protect themselves from cosmic rays with a spacesuit. It is very thick, and made up of several layers of fire-retardant fabric, folded metal sheets, and plastic and fiber mats like those used in bulletproof vests.
However, spacesuits provide limited protection. They mainly protect that astronaut from UV rays, but they do not block particle radiation and gamma and x ray. This is the reason why spacewalks are always planned during low solar activity and they are usually very brief.
How do astronauts urinate?
For short-term expeditions they use special diapers called MAG. In the case of a longer trip, spacecraft have special baths that operate at zero gravity. They do not absorb waste by means of water, but rather work as very powerful vacuum cleaners that absorb everything that is floating in their vicinity.
How do astronauts wash?
As we all know, almost all of the water that astronauts consume in space is carried from Earth, so they have to ration this precious resource very well. Therefore, instead of taking a shower, they lather with a damp cloth.
What physical changes do astronauts undergo in space?
Astronauts tend to lose muscle mass, since in space they do not use the force that is needed on Earth to overcome the resistance generated by gravity. Sometimes their faces swell as the fluid moves from the lower extremities to the upper part of the body, due to the lack of gravity. Another damage they suffer is the loss of bone density (more than 1% for each month in space).
After long periods of time traveling through space, an astronaut’s heart becomes almost 10% more spherical. This is due, according to expert testing, to extended exposure to microgravity. This becomes a problem as it can lead to serious heart problems.
The gloves of the spacesuit are very heavy and bulky, causing damage to astronauts’ nails. The gloves press the fingers so hard that they end up cutting off circulation, and applying powerful pressure on the tips of the fingers. For this same reason, their hands end up full of chafing, blisters and progressive nail loss. Some astronauts have even pulled their nails before starting their journey to avoid causing injuries and possible infection.
But there are some positive effects as well. For example, snoring disappears. The vacuum of space prevents sound waves from propagating, and therefore, being heard. In this way, in the absence of a wave medium, such as air, outer space puts an end to the habitual snoring of people.
Also, astronauts get taller in space. The decrease in pressure on the spine due to the absence of gravity causes the height of the astronauts to increase by approximately 5cm.
Finally, sleeping in outer space is quite a challenge, since the Sun rises and sets approximately every 90 minutes.