This study evaluates labyrinth seals for space mechanisms to enhance lubricant retention and reduce contamination under vacuum conditions. It examines the influence of seal geometry including length, width, surface roughness, and stepped features through analytical models, numerical simulations, and experimental validation. Surface roughness and geometric complexity strongly affect molecular transmission, while electrostatic fields and rotational dynamics further improve sealing performance. Experimental evaporation measurements align closely with simulations and validate correction models that incorporate surface roughness effects. These results guide the design of labyrinth seals for space applications.