If we are interested in the problem of space debris in the near-earth region, we have to investigate the lifetime of small particles (they have specifically large ballistic coefficients) in near-earth orbits as a function of their initial orbital elements. This paper contains such investigation carried out basing on an averaged system of differential equations for osculating orbital elements. The system takes into account the main disturbing factors: Earth oblateness, atmosphere drag, gravitation of Moon and Sun, solar radiation pressure. The special emphasis is placed in evaluation of the particle lifetime as a function of the initial orbit altitude, inclination, and eccentricity, as well as the particle ballistic coefficients.

Theoretical and applied problems of mechanics