Molecular contamination of spacecraft surfaces in thermostatic control and orbital injection of launch vehicle nose cone

The authors developed calculation and experimental procedures for engineering evaluation of surface roughness levels and mass of spacecraft molecular contamination level in thermostatic control of the Dnepr LV's nose cone by high-pressure air and in orbital injection of the space head module. It is shown that spacecraft surface molecular contamination corresponds to A/65 ≤ &xi ≤ A/25 levels in thermostatic control of the space head module by air of a purity class of 5000, and the particle mass of condensed phase of volatile compounds deposited on spacecraft surfaces during 930 seconds of flight is within 0.333 ≤ M_Σ ≤ 2.690 mg/m² in orbital injection, which is not worse than a purity level of ξ ≤ A/3.6 according to the MILSTD 1246C standard.