# Cosmos 1731
**Wikidata**: [Q12753422](https://www.wikidata.org/wiki/Q12753422)  
**Source**: https://4ort.xyz/entity/cosmos-1731

## Summary  
Cosmos 1731 was a Soviet reconnaissance satellite launched in 1986 as part of the Yantar-4KS1 class of spy satellites. It was deployed using a Soyuz-U rocket from Gagarin's Start, a historic launch site in Kazakhstan. The satellite played a role in the Soviet Union's photographic surveillance efforts during the Cold War.  

## Key Facts  
- **Class**: Yantar-4KS1, a Soviet spy satellite designed for photographic reconnaissance.  
- **Launch Date**: February 7, 1986, at 08:45:00 UTC.  
- **Launch Vehicle**: Soyuz-U rocket, a variant of the Soyuz family used for military and scientific missions.  
- **COSPAR ID**: 1986-013A, an international designation for Earth-orbiting objects.  
- **SCN**: 16589, a unique satellite catalog number.  
- **Launch Site**: Gagarin's Start (Baikonur Cosmodrome Site 1), the first launch pad used for crewed spaceflights.  

## FAQs  
### Q: What was the purpose of Cosmos 1731?  
A: Cosmos 1731 was a Soviet spy satellite designed to conduct photographic reconnaissance as part of the Yantar-4KS1 class.  

### Q: When and where was Cosmos 1731 launched?  
A: It launched on February 7, 1986, at 08:45:00 UTC from Gagarin's Start at the Baikonur Cosmodrome in Kazakhstan.  

### Q: What rocket was used to launch Cosmos 1731?  
A: The satellite was deployed using a Soyuz-U rocket, a reliable Soviet launch vehicle variant.  

## Why It Matters  
Cosmos 1731 represents a component of the Soviet Union's extensive space-based reconnaissance program during the Cold War. As a Yantar-4KS1 satellite, it contributed to photographic intelligence gathering, a critical function for military and geopolitical strategy. Its launch on a Soyuz-U rocket underscores the Soviet space industry's emphasis on reliability and cost-effectiveness in accessing space. While individual Yantar satellites like Cosmos 1731 were not publicly detailed due to their classified nature, their collective role highlights the integration of space technology into national security efforts during this era.  

## Notable For  
- **Yantar-4KS1 Class**: Part of a series of film-return reconnaissance satellites used for high-resolution imaging.  
- **Soyuz-U Launch Vehicle**: Demonstrated the versatility of the Soyuz rocket family, which remains in use in modified forms today.  
- **Historic Launch Site**: Launched from Gagarin's Start, the same pad used for Yuri Gagarin's 1961 mission, symbolizing continuity in Soviet space operations.  

## Body  
### Launch Details  
- **Date/Time**: February 7, 1986, at 08:45:00 UTC.  
- **Site**: Gagarin's Start (Baikonur Cosmodrome Site 1/5).  
- **Rocket**: Soyuz-U (11A511U), a "Universal" variant optimized for payload flexibility.  

### Satellite Class  
- **Yantar-4KS1**: A Soviet film-based reconnaissance satellite system. These satellites captured images on photographic film, which was returned to Earth in capsules for processing.  

### Mission Context  
- **Purpose**: To gather photographic intelligence for military and strategic planning.  
- **Operational Period**: Typical Yantar-4KS1 missions lasted approximately 60 days, though specific duration for Cosmos 1731 is not detailed in available sources.  

### Technical Specifications  
- **COSPAR ID**: 1986-013A (international identifier).  
- **SCN**: 16589 (Satellite Catalog Number).  
- **Wolfram Code**: Entity["Satellite", "16589"].  

### Cultural Notes  
- **Wikipedia Coverage**: Documented in Macedonian, Serbo-Croatian, and Serbian language editions, reflecting regional interest in space history.

## References

1. Jonathan's Space Report