In the end of the past century several tens of space vehicles with nuclear energy sources have been transferred to the low earth orbits. After completion of the mission plan the majority of them have been transferred to the disposal orbits (800-1000 km), where their orbital lifetime is several hundred years.

But currently at these orbits there is the maximum density of orbiting garbage of anthropogenic origin, which can lead to the collision of its elements with potentially dangerous radioactive objects. In case of their destruction some debris can get into upper layers of the earth atmosphere in several years, which can lead to radioactive contamination of the atmosphere and the Earth itself.

Orbiting garbage distribution at altitudes from 100 to 2000 km

For the first time scientists started to discuss large-scale space contamination in 1980s, when the concentration of garbage at the Earth orbit reached high density. Currently more than 600 thousand object with diameter of more than 1 cm are revolving around Earth. Because of the high store of kinetic energy collision of any of these objects with a functioning spacecraft can affect it or make inoperative. In connection with it the possibility of detection, identification and prediction of dynamics of radiation orbiting garbage elements for securing of safe use of low earth outer space is a very important task.

Currently, there is a constant control of parametres of space objects’ orbits with the help of radio-locating and optical means. For this purpose gamma, X-Ray, neutron, infra-red, optical and other spectrometres are used. However, for detection and identification of the most radioactive radiation from different objects it is necessary to use special equipment, installed at a space vehicle.

Scientists from MEPhI Department of experimental nuclear physics and cosmophysics, considering existing methods of detection and identification of radiation orbiting garbage elements, have proposed a project of measuring complex on the basis of xenon gamma spectrometres, which have high energy resolution and necessary sensitivity for detection and identification of such objects.

This measuring complex or scientific equipment “Nuclide” is currently developed in MEPhI together with “VNIIEM”. “Nuclide” defines isotropic and quantitative contents of radioactive objects in low surface outer space.

Supply of space vehicles of “Meteor” series by gamma spectrometer equipment “Nuclide” gives a possibility to identify, detect and predict dynamics of elements of radiation orbiting garbage. It is necessary to point out that for such research there is no need for power consumption for approximation of this space vehicle to researched objects.

One of developers, Professor at the Department of experimental nuclear physics and cosmophysics S.E.Ulin thinks, that to raise the accuracy of detection of radiation orbiting garbage it is necessary to conduct such measuring simultaneously with the help of several space vehicles, which are in different areas of low surface outer space. “In this case there appears a possibility top define the parametres of these objects’ orbits and to enhance overall statistical supply of experimental data,” scientist said.

Currently, the possibility of realization of the “Nuclide” project on board of one of Russian satellites is being considered.