The Soviet Venera program focused on landing a probe on Venus, and ten Venera probes successfully landed on the planet.
The first probes sent back data and images from within the planet’s atmosphere before being burned up by the incredible temperatures or crushed by the monumental atmospheric pressure.
Venera 7 touched down on July 22, 1972, and relayed the first data ever gathered by a probe actually on the surface of another planet, although it did so for only for 23 minutes.
The first surface images ever taken of Venus were transmitted by Venera 9 and Venera 10 in October 1975.
After analyzing the radar images returned from Venera 15 and 16, scientists determined that the ridges and grooves on the surface of Venus were the result of tectonic deformations.