Design Parameters and Efficiency of a Space System for Warning about Small Celestial Bodies Approaching the Earth along Collision Trajectories . ... tracking of an earlier detected hazardous celestial body (HCB) for synchronous-basic position measurements. The space telescopes (ST) would be placed at a long distance (such as 5 10 7 km) from the Earth to provide for detecting small (100 m) celestial bodies when they are moving to the Earth from the sunward direction. ...