What is weightlessness?Soaring cup, able to fly and walk on the ceiling, easy to move even the most massive objects - such a romantic idea of this physical concept.If you ask an astronaut, what weightlessness, he tells how difficult it is in the first week aboard the station and how long for his return has to recover, getting used to the conditions of gravity.Physicist, most likely, will lower these nuances and to reveal the concept of mathematical precision by using the formulas and numbers.
definition
We begin our acquaintance with the phenomenon with the disclosure of scientific subject matter.Weightlessness physics is a condition of the body when its motion or external forces acting on it does not lead to mutual pressure of the particles against each other.The latter always occurs on the planet, when an object is moving or at rest: it presses the force of gravity and opposite reaction of the surface on which the object is located.
exception to this rule - cases of free fall, that is falling at a rate which gives the body the force of gravity.In this process, there is no pressure of the particles against each other, there is weightlessness.Physics says that on the same principle based condition that occurs in space ships and sometimes planes.Weightlessness appears in these devices, when they move at a constant speed in any direction and thus are in a state of free fall.Artificial satellite or spacecraft delivered into space with the launch vehicle.It gives them a certain speed, which is retained after switching off the machine's own engines.Ship thus starts moving only under the force of gravity and zero gravity occurs.
Disadvantages
At the beginning of the space age was a question about the reaction of the body to the absence of gravity.Weightlessness in space was a phenomenon not fully understood, though predictable.Today, its impact on the human body as a whole is studied.
finely tuned mechanism of body experiences, in the absence of gravity enormous stress.Space weightlessness leads to disruption of the hydrostatic pressure of the fluid in the body (especially the blood), the disappearance of the usual load on the musculoskeletal system.Some time after the arrival of the ship or the station, astronauts are exposed to the so-called syndrome of adaptation to space.
effect on the body
What is weightlessness for a beginner?It dizziness, disorientation.You may experience a variety of illusory sensations.The body begins to adapt to the new conditions, but it takes time to rebuild.As a rule, the work of the body is getting better within ten days.
then, however, the changes continue to occur.Because of the lack of gravity decreases the total body burden.As a result, the astronauts in weightlessness lose weight, they have a reduced capacity for work and, on the contrary, increased fatigue.And changes the ratio of the chemical elements in tissues: bones lose some minerals they need.Often, after returning to Earth after a long stay at the station astronaut becomes higher by a few centimeters.The reason lies in the same weightlessness.The results of the growth spurt are not the most pleasant: may cause pain, pinched nerves.
House
Implications for flights astronauts do not stop there.After returning to Earth they have for some time to adapt back to the force of gravity.What is weightlessness for astronaut complete the project?First of all, it's a habit.Consciousness is still some time refused to accept the existence of gravity.As a result, there are cases when the astronaut instead put a cup on the table, just let her go and realized the mistake only when he heard the sound of broken dishes on the floor.
Power
One of the difficult tasks at the same time interesting for the organizers of manned space flight - to ensure the astronauts easily digested under the influence of weightlessness food in a convenient form.The first experiments did not cause much enthusiasm among the crew members.Indicative in this respect, the case when American astronaut John Young despite the strict ban carried on board Sandwich, which has, however, did not, in order not to violate the charter further.
Today, with a variety of on orbital stations is no problem.The list of dishes available for Russian cosmonauts, has 250 points.Sometimes the cargo ship, which starts to the station, delivers fresh food ordered by someone from the team.
basis of the diet are freeze-dried products.All liquid food, beverages and puree packed in aluminum tubes.Packaging shell products thought out so as to avoid the appearance of crumbs floating in zero gravity and able to hit someone in the eye.For example, a cookie is small enough, and film-coated, melting in your mouth.
Familiar atmosphere
at stations such as the ISS, all the conditions are trying to bring to the familiar Earth.This national dishes on the menu, and necessary for the body to function, and for the normal operation of the equipment the movement of air, and even the designation of the floor and ceiling.The latter is rather the psychological significance.The astronauts in weightlessness is like to work in any position, but the conditional release of the floor and ceiling reduces the risk of loss of orientation and contributes to a more rapid adaptation.
Weightlessness - one of the reasons why the astronauts take not all.Adaptation on arrival at the station, and after returning to Earth comparable with acclimatization, reinforced several times.A man in poor health so can not sustain the load.
