What is space junk?

The so-called "space junk" refers to abandoned satellites, rocket upper stages, fairing parts, bolts, washers, various metal blocks, fallen paint, etc. So how much space junk is there in low earth orbit? It is estimated that there are about 25,000 pieces of space junk since the beginning of the space age 50 years ago. Because many of these objects burned when they entered the atmosphere, there are about 9000 pieces that can be seen now. Moreover, if the spacecraft flies at an altitude of 600 kilometers, it will revolve around the earth for 25-30 years. If you are at an altitude of 1000 km, you can fly to 400 1 year. A little higher, it will almost become an eternal object. Now there are more and more such "longevity" garbage in space, and it will be extremely difficult to remove it.

The threat of space junk

The possibility of various aircrafts flying in space meeting with space junk is increasing day by day, which has aroused people's concern and anxiety. According to the expert's assertion, a 1.3mm shot put is equivalent to a bullet of a 22mm caliber rifle, flying at the speed of 10km per second.

1In July 1996, the French satellite "Service" was hit by the debris of the Ariane rocket launched by China 1986. 1In July 1993, a depression with a diameter of 4 mm was found in the side cabin of the Russian space station Heping. The American space shuttle Endeavour also found such dent marks, which were "created" by white paint dust with a diameter of about 0.2 mm, and there were hundreds of such incidents. It is said that when the space shuttle Endeavour is flying now, in order to avoid "unpleasant" things, there is a flight that deviates slightly from the route every day and night.

In fact, when tiny space junk runs at a speed of 3 kilometers per second, its energy is equivalent to the energy released by the same amount of explosives. Scientists believe that a piece of garbage with a diameter of 10 cm is enough to destroy any spaceship. In a word, the increase of space junk will bring more and more troubles to mankind.

The concept of "space junk" was first put forward by the air defense personnel on duty. The national space monitoring department monitors more than 50,000 celestial bodies every day, and space junk often confuses them. 16 years ago, a meteorological observatory in Canada announced that a star exploded near Perseus. Later, I realized that this was just the effect of an abandoned satellite being reflected by sunlight. According to the Russian newspaper, in 1987, there was a case that the "Quantum" module could not be docked with the "Peace" because the connector was not tightened. At that time, the experienced ground control center thought that something must have interfered with the docking outside the cabin, so it sent an investigation team to inspect and found a piece of metal there.

Before the 1960s, no one had heard of objects falling in space, but since 1973, hundreds of pieces of space junk have fallen to the earth every year. Thankfully, no one has been injured so far.

How to deal with space junk

In terms of laws and regulations, it is mainly to formulate rules and regulations to regulate space launch and minimize the generation of space junk. Technically, the suggested measures are various. Among them, first, we must strengthen observation, observe space junk through astronomical telescopes and report to the police in time. However, the astronomical telescope can only observe the garbage above 10 cm, and the small one can't be seen yet. To this end, some scientists have proposed to install a protective cover made of ceramic materials and polymer materials on the spacecraft to resist the impact of small garbage. In addition, it is suggested that small satellites and ion rockets should be used to slowly approach the garbage, and then the orbit of the garbage should be changed or destroyed to reduce the threat.

Space environment is in urgent need of maintenance.

At first, people in the space station didn't pay attention to the garbage problem. After the special garbage container is filled, it is thrown into space through the hatch.

With the passage of time, scientists began to pay attention to the ecological problems in low-earth orbit and decided not to throw garbage into space. On the "Peace" space station, garbage is bagged and preserved. After the cargo ship "Progress" arrived, it unloaded the cargo and put in the garbage, so the garbage and the cargo ship burned together in the atmosphere. According to Russian newspapers, the American space shuttle Endeavour has been throwing rubbish into space. So sooner or later, human beings have to bear the consequences for all kinds of garbage they throw in space.