In the Earth, a force called gravity attracts us without stopping towards the earth, the gravity is what makes us feel our weight. But, in the space, this force doesn’t make nearly any effect. We are in a state called microgravity, in which you don’t feel your own weight. Before their missions, the astronauts must train to get used to this phenomenon. They also train in simulators, to pilot a spacecraft and use scientific equipments. From now on I’ll explain the training sessions of the astronauts before going to space.
Training in swimming-pools
These trainings which take place in giant swimming-pools, have like purpose to familiarize the body to the extravehicular activity. Inside the swimming-pool, the astronaut feels himself floating in a similar state from the space’s. Thanks to this, the astronaut can practice the movements that he will do during his missions in the same state in which he will be in the space.
Inside the swimming-pool there are some miniatures of the components of the International Spacial Station, which orbits around the Earth at 27 700 km/h. This way the astronauts can also get used to the place in which they will be in the space. Every training session lasts for three hours.
This training has also the purpose of familiarize the body of the astronauts to the microgravity. This training is done inside of specialized planes. This planes describe in the sky a curve in form of parabola, is to say, the plane goes up quickly and then it decelerates between 20 or 30 seconds before going up another time. This process is repeated for 15 times, that is to say, that the plane describes 15 parabolas before going down another time to earth. During the time which the plane decelerates, the astronauts that there are inside the plane feel similar as if they were in the space. So, they are in a state of microgravity.
Although during a lot of time this flies were reserved for the astronauts, nowadays there are also enterprises that organize this flies for whom which want to try this experience. However, they are very expensive, they cost about 4 000€ per person
The tilting table
The tilting table is another of the important training sessions of the astronauts before going to space. It serves the astronauts to get used to the feeling that they will have in the space. Lying on the tilting table, the astronaut passes through all the inclination degrees. Like this, he trains himself to feel how the blood goes up to his head, as to get used to the constant inclination change that he will feel in space.
Training in the centrifuge
Until now I’ve talked about the training of the astronauts to get used themselves to the sensations that they will feel in the space, but they also train for the moment in which the rocker will takeoff. The place in which they train for the takeoff is called the centrifuge. In this place, the astronauts go up into a machine that turns over its centre, describing the form of a circle. This machine simulates the sensation of the takeoff, in which the astronauts will feel a higher gravity that in the Earth. This is due to the acceleration of the rocket, which the astronauts to feel that they are “pushed” towards their seats. This force is measured in g’s. It is considered that in the Earth we normally feel a gravity of 1g, but the astronauts, during the takeoff, are subdued to much more “g”. For this reason they have to train in the centrifuge, to familiarize the body to feel more “g” of the normal.