Astronauts must be wearing their spacesuits when they get out of their spacecraft and are exposed to the “space environment,” but why?
Is the space environment dangerous for humans?
A common definition of space is known as the Karman Line, an imaginary boundary 100 kilometers (62 miles) above mean sea level. Unfortunately, the danger zone after this line is not a suitable environment for humans to live. The most common reason for this is that there is little or no respirable oxygen in that area.
Almost all living organisms utilize oxygen for energy generation. As we breathe in, oxygen enters the lungs and diffuses into the blood. Our lungs, working as a tiny factory, throw out the carbon dioxide molecule formed by 2 oxygen and 1 carbon atom at the end of the process.
Although oxygen deprivation seems to be the only real danger, it is actually only one of the dangers.
So what could be done to avoid these and similar dangers?
If you are going to go to space one day, perhaps the most important thing to take with you may be the spacesuit. Spacesuits are like a small spacecraft and protect astronauts from dangers in space. The Primary Life Support System (PLSS), which looks like a backpack, provides the suit with pressurized oxygen and ventilation while removing carbon dioxide, water vapor, and trace contaminants.
The spacesuits used on the International Space Station today remain there all the time. In other words, astronauts do not have their own space suit. The same spacesuit can be worn by several astronauts, according to the assignments from the Mission Control Center.
So can every astronaut wear the same spacesuit?
As you can imagine, the physical structure of every astronaut is not the same. Some astronauts may be tall, some are short, some may be a little leaner or overweight than others. It is precisely for this reason that astronauts have space suits in three different sizes (small, medium and large) that they use on the International Space Station. Since the connection points of these spacesuit are the same, an astronaut can make a special combination from these three different sizes if needed.
What does the spacesuit protect us from?
First of all, it can eliminate the oxygen deprivation that we mentioned at the beginning for a certain period of time. Each spacesuit has two oxygen tanks that work with a carbon dioxide removal system to allow a 6 to 8.5 hour spacewalk. Afterwards, the astronaut must return to the space station in order to refill the empty oxygen tanks. Another danger is related to the temperature in space.
Is space hot or cold?
Unfortunately, the temperature in space is either too high or too low for the human body to stand. For example, ,if an astronaut would go on a spacewalk without a spacesuit when the sun is shining brightly, he or she would suddenly encounter a temperature of about 120 degrees Celsius with the effect of radiation.
Without the sun, the temperature suddenly drops to about -120 degrees Celsius. This situation happens very, very suddenly because there is no atmosphere in space. Here, the only thing that keeps the astronaut safe in these difficult conditions is again the spacesuit. Another important item on the spacesuit is the Liquid Cooling and Ventilation Garment (LCVG), which incorporates clear plastic tubing through which chilled liquid water flows for body temperature control, as well as ventilation tubes for waste gas removal. Thus, the astronaut can always work comfortably in the spacesuit.
In addition to all these, the astronaut must wear a spacesuit to be protected from pressure, radiation and meteor dust.
Is there pressure in space?
Even though we can’t feel it, air is constantly pressing down on us with a tremendous force. We cannot see this force with our eyes, but we constantly experience the results of this effect, especially when driving on steep hills or getting off an airplane. This pressure created by the air and the internal pressure created by the beat of our heart is constantly in balance. As we just explained, there is no air in space. This means that there is no air pressure in space. Therefore, spacesuits are inflated with a certain amount of air, just like a balloon, to apply the necessary external pressure to the astronaut. Thus, the body fluids of astronauts can remain in liquid form during a spacewalk.
What do astronauts eat and drink during a spacewalk?
Astronauts may have to take long space walks from time to time. The record belongs to two astronauts, Jim Voss and Susan Helms, who took a spacewalk for 8 hours and 56 minutes. Of course, astronauts can get hungry or thirsty during this long spacewalk. If necessary, you may think that they can go to the space station and have their food. But every minute in space is planned and very important. Taking off a spacesuit, that actually takes 15 minutes to put on with someone’s help, can cost the astronaut half an hour, so the astronauts do not prefer to return to the space station and take a lunch break. NASA has found a solution to this issue as well.
Under normal circumstances, menus containing more than 1000 types of food are prepared for the International Space Station astronauts. These menus that include snacks can be consumed by astronauts at the station. There is also a high-calorie chocolate bar, fixed in a space suit helmet close to the mouth, so that astronauts can gain energy on challenging spacewalks. Especially on long spacewalks, astronauts enjoy the meal breaks where they consume these chocolates. Since they cannot use their hands, astronauts consume the chocolate bar by biting on it several times.
The next need of the astronaut consuming a high-calorie chocolate bar is of course water. At this point, a water bag located in the spacesuit helmet and a straw attached to this bag comes to aid. The tip of the straw can be opened and closed using only the mouth.