Venera 13 was a probe in the Soviet

Soviet space program

The Soviet space program is the rocketry and space exploration programs conducted by the former Union of Soviet Socialist Republics from the 1930s until its dissolution in 1991...

 Venera program for the exploration of Venus

Venus

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows...

.

Venera 13 and 14 were identical spacecraft built to take advantage of the 1981 Venus launch opportunity and launched 5 days apart, Venera 13 on 1981-10-30 at 06:04:00 UTC and Venera 14

Venera 14

Venera 14 was a probe in the Soviet Venera program for the exploration of Venus.Venera 14 was identical to the Venera 13 spacecraft and built to take advantage of the 1981 Venus launch opportunity and launched 5 days apart...

 on 1981-11-04 at 05:31:00 UTC, both with an on-orbit dry mass of 760 kg.
Each mission consisted of a bus and an attached descent craft.