There must be space junk in the immigrant's residence. How are these space wastes generated, how to avoid them and how to deal with domestic wastes?

Space junk is all kinds of objects and debris abandoned by human beings in space activities.

They fly around the earth in a certain orbit like satellites, forming a dangerous garbage belt. Space junk can be divided into three categories: first, the relatively large objects that modern radar can monitor and track, mainly including various satellites, satellite protective covers and various components. At present, it has reached more than 8,000; Second, small objects, such as engines, are produced when space explodes, and the number is estimated to be at least several million; Third, nuclear-powered satellites and the radioactive debris they produce. By the year 2000, these satellites will send 3 tons of debris into Earth orbit.

1957 1714 October, the former Soviet Union successfully launched its first artificial earth satellite.

It opened the prelude to the human space age and sent the first batch of garbage into space. At that time, the astronauts completed the task, leaving the satellite's loading cabin, spare cabin, instruments and equipment in the satellite orbit. Since then, with the feat of human space history, space junk has increased day by day. Humans have launched more than 4000 satellites into space, and only 400 satellites are still in normal operation. The rest either crashed on the surface of the earth, or stayed in space and became space junk. According to statistics, there are currently about 3,000 tons of space junk flying around the earth, and the number is still increasing at the rate of 2%-5% every year. Scientists predict that the increase of space junk at this rate will lead to a catastrophic chain collision. If this situation continues, nothing will be able to enter space orbit by 2300.

Space junk has brought hidden dangers to the development of space industry and turned into artificial satellites and artificial orbits.

The potential killer of the space station poses a serious threat to the safety of astronauts. You know, space junk runs at the speed of the universe. An oncoming metal particle with a diameter of 0.5 mm is enough to pierce the sealed flight suit; Dust that people can't distinguish with the naked eye (such as paint chips and paint powder) can also kill astronauts; A fragment the size of an aspirin tablet can "paralyze" a satellite and send a spacecraft costing hundreds of millions of dollars into a dead end. In the history of human spaceflight, accidents and disasters caused by space junk are common. 1983, the American space shuttle Challenger collided with a paint tape with a diameter of 0.2 mm, which damaged the porthole and had to keep flying. The "Salute -7" orbital station of the former Soviet Union was also damaged by such "dust" many times. 1986, the Ariane rocket exploded shortly after it entered orbit, becoming 564 fragments with the size of 10 cm and 2300 small fragments. The wreckage of this rocket made two Japanese communication satellites "die"! 199 1 05 September 15, the space shuttle discovery launched by the United States almost collided with the rocket wreckage of the former Soviet Union. At that time, Discovery was only 2.74 kilometers away from the uninvited guest. Fortunately, the command system on the earth issued a warning signal in time to prevent it from dying. According to the calculation, the probability of catastrophic collision of each flying object in space orbit is 3.7%, and the probability of non-catastrophic collision is 20%. Based on this calculation, the collision between space junk and spacecraft may occur every 5- 10 years in the future, and it will reach once every two years by 2020.

Space junk not only brings great hidden dangers to the space industry, but also pollutes space.

It will bring disaster to human beings, especially when the nuclear-powered engine falls off, which will cause radioactive pollution. At present, the United States and the former Soviet Union have 1 ton of uranium -235 and other nuclear separations in nuclear reactors in space. The former Soviet Union launched 3/kloc-0 nuclear-powered reconnaissance satellites, two of which have polluted the ground: 1978, a large number of radioactive debris from Cosmos 954 fell into the Canadian Sea of Clafin; 1983, the reactor core of Cosmos 1402 fell into the South Atlantic.

In order to control and reduce the potential threat of space junk to human beings, space experts put forward some suggestions.

Many countermeasures can be summarized in four words: "avoidance, prohibition, reduction and clearance".

The so-called "avoidance" means accelerating the development of modern space surveillance systems and conducting space junk.

Closely monitor and track, and take effective technical measures to make the spacecraft avoid space junk in time.

The so-called "ban" means to formulate international laws and regulations on space and prohibit experiments in space.

Test and deploy all kinds of weapons, limit the launch of nuclear-powered satellites, and make space a peaceful space serving human civilization.

The so-called "reduction" means that countries that launch spacecraft should take measures to minimize space.

An increase in garbage. The last stage rocket is evacuated with unburned propellant and high-pressure gas to avoid the explosion of the last stage rocket.

The so-called "cleaning" is the task of developing space garbage removal technology and delivering it.

In the last stage of the rocket, measures are taken to transfer the orbit, so that it can return to the atmosphere and burn; For the satellite that has reached the predetermined life, let it get the escape speed, stay away from the near-earth space or use the clearing device to clear it. Some experts put forward the idea of using the power of laser to make large pieces of garbage change their tracks first and then gasify.

Most of the space life garbage is brought back to the earth, but special instruments such as urine are converted into water for drinking.