EntityQ1067650· pop 29· linked from 185 articlesMars 4Sign in to savespace probeConnectionsMars programEntityMars Exploration ProgramEntityRussianEntityMarsEntitySoviet UnionConceptplasmaEntityultraviolet radiationEntityinfrared radiationEntityBaikonur CosmodromeEntityRosettaEntityorbital periodEntityapsisEntitySkylabEntityradio telescopeEntityPioneer 11EntityPhoenixEntitylow Earth orbitEntityPerseveranceEntitypolarizationEntitySpiritEntityCategories1973 in spaceflight1973 in the Soviet Union4MVDerelict satellites in heliocentric orbitMars flybysMars programNon Earth orbiting satellites of the Soviet UnionSoviet missions to MarsSpacecraft launched in 1973