Gravity

The force of gravity, also known as gravity, is made up of centrifugal force and gravity. It is the force that acts on a body that is on the surface of the earth. The centrifugal force is caused by the rotation of the earth, which reaches a speed of approx. 1670 km/h measured at the equator and the gravitation, which is caused by the mutual attraction of masses. The gravitational pull works up to a height of approx. 700km, called the exosphere, from there weightlessness begins. A non-propelled body has to reach an escape speed of at least 11.2 km/s in order not to fall back to earth, which corresponds to the equivalent of 40,320 km/h. The force of gravity acts on a freely falling body, causing it to fall back to earth at 9.81m/s. Gravity acts on every body that is on earth, including the human body. Our body is used to gravity and has adapted to it. Longer stays in weightlessness, for example astronauts on a space mission, damage the human body. The main problem is the rapid loss of muscle mass and bones. Due to the lack of gravity, the muscles do not exert any pressure on the bones, which is why the astronauts train several hours a day to counteract muscle breakdown. Nevertheless, after a long stay in space after landing on earth, the astronauts cannot walk without help and it takes time for the muscles and bones to regenerate. That is why work has been going on for a long time on what is known as artificial gravity in order to counteract these effects.