How can the International Space Station avoid garbage and rapidly change its orbit in space?

　　space garbage

　　Refers to various man-made waste bodies and their derivatives in space, including invalid spacecraft, rocket wreckage, operational debris, disintegrated debris, etc.

Their operating speed is close to the first cosmic speed (7.9 km/s), and there is a risk of hitting other spacecraft. Some space junk will also pose a threat to ground safety when it returns to the atmosphere.

　　Collision warning

　　■Launch early warning

　　Refers to the prediction of whether it will intersect with the debris or the position and orbit of the spacecraft in the short term after launch. Once a danger is found, the launch time can be changed to avoid collisions

　　■On-orbit warning

　　Refers to predicting whether the spacecraft will have a dangerous rendezvous with debris after stable operation. If there is a risk of rendezvous, the orbit must be changed to avoid the debris

　　Clear method

　　■One type is contact type, such as mechanical arm grabbing, net catching, etc.

　　■One type is non-contact type, such as laser shift, ion beam shift, etc.

　　According to news from the Russian Space Agency on December 3, local time, the International Space Station (ISS) had undergone an orbit change earlier in the day to avoid a collision with a fragment of a rocket launched by the United States in 1994.

　　The orbit of the International Space Station is adjusted using the thrusters of the "Progress MS-19" cargo ship, which is docked with the laboratory on the orbit.

The orbital altitude of the space station dropped by about 310 meters in 160.9 seconds to provide enough space to avoid collisions with debris from the USS Pegasus launch vehicle launched in 1994.

　　The risk of "passing by" rubbish is increasing

　　According to the Russian Satellite News Agency, in November this year, the International Space Station "brid-by-shoulder" with space junk several times.

　　On November 15, a piece of space junk flew by near the International Space Station, but no collision occurred.

Due to the threat of space junk, the astronauts had to escape into the Soyuz spacecraft.

　　On November 25, debris from the US Spacex rocket flew 5 kilometers away from the International Space Station. Fortunately, it did not interfere with the normal operation of the International Space Station.

　　Earlier in May of this year, during a routine inspection of the International Space Station by the National Aeronautics and Space Administration and the Canadian Space Agency, it was discovered that the robotic arm provided by Canada had a small hole with a diameter of 5 mm, which was caused by the impact of orbital debris.

The analysis results show that the operation of the robotic arm is not affected and can complete the original task.

Some analysts said that the impact incident is also a reminder that as the number of satellites in the earth's orbit increases, the risks caused by these space junk are also increasing.

　　How to avoid space junk flying at 7.9 km/s?

　　Space junk is a variety of man-made waste bodies and their derivatives in space, including failed spacecraft, rocket wreckage, operational debris, and disintegrated debris.

In space, the speed of space junk is close to the first cosmic speed (7.9 km/s), which is several times the maximum ejection speed of a sniper rifle bullet.

　　Once the space junk collides with the spacecraft, it will cause the surface of the spacecraft to wear and lose its function, and at the worst, it will cause the disintegration of the spacecraft in orbit, and even pose a threat to the personal safety of the astronaut.

How to avoid space junk is a very serious problem faced by spacecraft in space flight.

　　The current method for spacecraft to avoid space junk is to carry out collision warning.

Collision warning includes two phases: launch warning and on-orbit warning.

Launch early warning refers to predicting whether the spacecraft will encounter debris or the location and orbit of the spacecraft in the short term after launch. Once danger is found, the launch time can be changed to avoid collisions; on-orbit early warning refers to predicting whether the spacecraft will be in danger with debris after stable operation For rendezvous, if there is a risk of rendezvous, the trajectory needs to be changed to avoid debris.

　　What is the "coup" to clear space junk?

　　The accumulation of large amounts of space junk in orbit will increase the risk of spacecraft operations and even make orbital space unusable.

With the vigorous development of space activities, if left unchecked, there will be more and more space junk and the space environment will rapidly deteriorate.

　　At present, the methods of actively removing space junk are mainly divided into two types: one type is contact type, such as robotic arm grasping, netting, etc.; the other type is non-contact type, such as laser shifting, ion beam shifting, etc.

　　Regardless of the method, cleaning up space junk is not easy.

This long-term work still requires all countries to pay attention, strengthen cooperation, and put into practical action.

　　According to CCTV News