Make way for astronauts – Nauka – Kommersant

Wherever a person appears, debris is bound to appear, and space is no exception. According to the American (NORAD, NASA), European (DISCOS, ESA) and Russian (ASPOS OKP) catalogs of space debris, about 20 thousand registered space objects larger than 10 cm are observed in near-Earth space. To observe and record smaller debris, it is necessary to create a special spacecraft to observe small fractions of space debris.

Space debris is of cosmogenic and artificial origin. Cosmogenic is called the “building material” of the solar system, for example, micrometeorites, interplanetary or interstellar dust. Man-made is anything that man has created. Technogenic space debris is classified into the following categories: small (less than 5 mm), medium (from 5 mm to 10 cm) and large fragments (more than 10 cm).

The most clogged orbits are: low orbits 300–400 km (here space debris “lives” no more than three to four months), 800–1000 km and 1200–1500 km; sun-synchronous orbits, intermediate orbits (from 2000 km to 35786 km) and geostationary orbit (35786 km).

Space debris objects in near-Earth space create a real hazard for high-speed collisions of functioning vehicles with passive fragments. The cause of the early destruction of the object may be a collision with a particle smaller than 0.1 cm at a speed of 10 km/s. The probability of a collision of a spacecraft with a surface of 6 m at an altitude of 900 km is 10^–6 in 90 years. Of course, while this probability is very small, but every year it will grow, because the growth of space debris is 6-12% per year. The greatest probability of collision of spacecraft with space debris is in low orbits, about 500–1500 km high.

Recently, there have been several collisions of cataloged objects of space debris.

Collisions of space objects




Many ways have been developed to counter space debris: from the most common, such as smashing large pieces of space debris, removing space debris, or removing a spacecraft from space debris, to less common ones, such as shooting down debris with lasers or processing it into fuel . It is impossible to use only one method of countermeasures for all types of space debris. For example, it is impossible to catch small space debris with a net, and it is useless to stop large space debris with gas.

However, there are two main areas:

– Methods for crushing space debris directly in orbit;

— Methods of deceleration and removal of large space debris from low orbits for subsequent combustion in the atmosphere or removal of space debris from geostationary orbit to a disposal orbit.

In addition, both methods have disadvantages associated with the formation of fragments of a smaller fraction, the fall of unburned fragments to the ground and clogging of higher paths.

And why not develop a spacecraft that will absorb space debris? Such a device exists. The idea of ​​creating a space debris disposal device is based on processing space debris into pseudo-liquid fuel, which is a mixture of powdered crushed space debris with oxygen and hydrogen. Space debris mainly consists of the materials shown in Fig. 2.

The robotic search system locates the debris to be destroyed, as shown in Fig. 3.

The Garbage Collector reverses the engines, folds the fan-shaped solar collector and moves through the accumulation of space debris, releasing a trap in the form of deformable nets on a cable system. He catches up with debris in orbit, at an altitude of 800 km and catches it with a net on cables. The nets consist of triangular links, which when the net is compressed form a dense web. Such a structure of networks makes it possible to avoid entanglement of space debris in them, and consequently failure of the SCM. When space debris is detected, the dome net is automatically released on cables from telescopic guide beams on the cone net, which can pull the cables back inward. Also connected by cables, the dome-shaped and cone-shaped networks form a closed cavity – a garbage collector, which shrinks as space debris arrives for disposal. The recycling system consists of the following components: a trap, a two-roll mill, a drum ball mill, a membrane-electrode unit, a water regenerator, a control unit, a fuel tank and motors.

The space garbage collector uses space debris and processes it into fuel, the use of which allows the spacecraft to gradually rise to higher orbits, up to the burial orbit (over 40 thousand km), and cleans up outer space.

The easiest way to clear outer space of debris is to suspend space activity for ten years and wait for Earth’s gravity to do its job, but then humanity will slide, at best, into the 19th century. If nothing is done, at the current rate of growth of space activity, we will soon simply not be able to launch spacecraft (this phenomenon is called Kessler syndrome) and will at best slip into the same 19th century.

Now, in near-Earth space, an ecosystem is emerging, in biological terms. In this ecosystem, as in any other, there are creatures that live, feed, perform their functions and, when they die, give food to other creatures. In space activities we must also imitate nature. Such “carrion eating” creatures can and should be space junk collectors in the broadest sense of the word. But currently, 60 years of cosmic duration is a very short time to create a closed ecosystem called “outer space”.

Maria Barkova, PhD student, Russian Space Systems JSC

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