# Venera 12 Descent Craft

> Venera 11 and Venera 12 were identical spacecraft built for the September 1978 Venus launch window

**Wikidata**: [Q113136544](https://www.wikidata.org/wiki/Q113136544)  
**Source**: https://4ort.xyz/entity/venera-12-descent-craft

## Summary
The Venera 12 Descent Craft is the lander component of the Soviet Venera 12 mission, launched on 14 September 1978 to deliver instruments to the surface of Venus. Identical to the Venera 11 lander, it separated from its cruise stage and descended through Venus’s atmosphere, becoming one of the few spacecraft to survive the planet’s extreme surface conditions.

## Key Facts
- Launch date: 14 September 1978 from Baikonur Cosmodrome aboard a Proton-K rocket
- COSPAR ID: 1978-086C; NSSDCA ID: 1978-086C; SCN: 12028
- Instance of: lander (spacecraft that descends to and rests on an astronomical body)
- Has part: Venera 12 (full spacecraft bus that carried the descent craft)
- Launch vehicle: Proton-K carrier rocket
- Identical twin: Venera 11 Descent Craft, built for the same 1978 Venus launch window

## FAQs
### Q: What was the purpose of the Venera 12 Descent Craft?
A: It was designed to separate from the Venera 12 cruise stage, enter Venus’s atmosphere, and land on the surface while transmitting data about the planet’s harsh environment.

### Q: Is Venera 12 Descent Craft the same as Venera 12?
A: No. Venera 12 refers to the complete spacecraft; the Descent Craft is the lander component that detached to reach the surface.

### Q: How many identical landers were built for the 1978 Venus window?
A: Two—Venera 11 and Venera 12—each carrying an identical descent craft launched in September 1978.

## Why It Matters
The Venera 12 Descent Craft represents a critical milestone in planetary exploration: it demonstrated that robust Soviet engineering could withstand Venus’s crushing 90-bar pressure, 465 °C temperatures, and corrosive atmosphere long enough to return in-situ data. By successfully landing on 21 December 1978, it joined an exclusive club of spacecraft—only Soviet Venera landers have ever operated on the Venusian surface. The mission validated heat-shield technologies, pressure-resistant titanium hulls, and high-temperature electronics that informed later Soviet and international planetary probe designs. Beyond engineering, the data returned helped refine models of Venus’s atmospheric composition, cloud structure, and surface conditions, providing a comparative baseline for Earth-climate studies and future Venus missions.

## Notable For
- One of fewer than ten spacecraft to have landed on Venus and returned data
- Identical twin to Venera 11 lander, enabling cross-validation of Venus surface measurements
- Launched within the narrow September 1978 Venus transfer window, showcasing precise mission planning
- Survived entry and descent through Venus’s dense CO₂ atmosphere, a feat only achieved by Soviet Venera landers

## Body
### Mission Context
The Soviet Union’s Venera program seized the 1978 Venus launch opportunity by building two identical spacecraft—Venera 11 and Venera 12—each comprising a cruise stage and a descent craft. Launching both increased the probability that at least one lander would succeed.

### Launch and Identification
Venera 12 Descent Craft left Earth on 14 September 1978 at 02:25 UTC atop a Proton-K rocket from Baikonur Cosmodrome, Kazakhstan. International tracking catalogs assign it COSPAR ID 1978-086C and NSSDCA ID 1978-086C; NASA’s Satellite Catalog Number is 12028.

### Spacecraft Architecture
The descent craft is a hermetically sealed titanium pressure vessel mounted inside an aeroshell. After separation from the cruise stage, the assembly hit Venus’s atmosphere at ~11 km/s, deployed a parachute system, jettisoned the heat shield, and landed under free fall. On the surface, a small circular antenna transmitted data directly to Earth until the orbiter moved out of radio line-of-sight.

### Relationship to Venera 12
Venera 12 denotes the complete interplanetary spacecraft; the descent craft is the lander subsystem. Thus, “Venera 12 Descent Craft” is a part of, not synonymous with, Venera 12.

## References

1. Jonathan's Space Report