Venera program
The Venera program was a series of Soviet robotic missions to Venus conducted between 1961 and 1984, culminating in multiple atmospheric entries, the first soft landing on another planet, the first images from a planetary surface beyond the Moon, and radar mapping from orbit. Built primarily by the Lavochkin design bureau, Venera spacecraft established the basic picture of Venus’s extreme surface conditions and atmosphere and pioneered techniques later used by related missions such as the Vega balloons.