The earth orbiting space debris

Abstract

The space debris population is similar to the asteroid belt, since it is subject to a process of high-velocity mutual collisions that affects the long-term evolution of its size distribution. Presently, more than 10 000 artificial debris particles with diameters larger than 10 cm (and more than 300 000 with diameters larger than 1 cm) are orbiting the Earth, and are monitored and studied by a large network of sensors around the Earth. Many objects of different kind compose the space debris population, produced by different source mechanisms ranging from high energy fragmentation of large spacecraft to slow diffusion of liquid metal. The impact against a space debris is a serious risk that every spacecraft must face now and it can be evaluated with ad-hoc algorithms. The long term evolution of the whole debris population is studied with computer models allowing the simulation of all the known source and sink mechanisms. One of these codes is described in this paper and the evolution of the debris environment over the next 100 years, under different traffic scenarios, is shown, pointing out the possible measures to mitigate the growth of the orbital debris population. .Populacija svemirskog otpada slicna je asteroidnom pojasu, jer se i u njoj dogadjaju medjusobni sudari na velikim relativnim brzinama, koji uticu na evoluciju raspodele tela po velicini. U ovom trenutku vise od 10000 komada vestacki stvorenog otpada precnika iznad 10 cm (a vise od 300000 komada precnika veceg od 1 cm) kruzi oko Zemlje i svi se oni prate i izucavaju pomocu velike mreze senzora rasporedjene po citavoj Zemlji. Populaciju svemirskog otpada cine mnoge razlicite vrste objekata nastalih na razne nacine, od visoko energetskih raspada velikih svemirskih letelica, do spore difuzije tecnog metala. Udar nekog komada svemirskog otpada predstavlja danas rizik sa kojim se svaka nova svemirska misija mora suociti, a koji se moze proceniti pomocu odredjenih ad-hoc postupaka. Evolucija celokupne populacije svemirskog otpada izucava se pomocu kompjuterskih modela koji simuliraju sve poznate mehanizme nastanka i nestanka otpada. Jedan od ovih programa opisan je u ovom radu, kao i rezultujuce moguce evolucije populacije otpada i okruzenja u narednih 100 godina, koje se predvidjaju na osnovu razlicitih scenarija buduceg saobracaja. Takodje se ukazuje i na mere koje je moguce preduzeti da bi se sprecio i zadrzao pod kontrolom buduci rast populacije orbitalnog otpada. .