# Cosmos 731
**Wikidata**: [Q1119705](https://www.wikidata.org/wiki/Q1119705)  
**Source**: https://4ort.xyz/entity/cosmos-731

## Summary  
Cosmos 731 (also written Kosmos 731) was a Soviet‑built Zenit 2M optical reconnaissance satellite launched on 21 May 1975 from Baikonur Cosmodrome’s Site 31 using a Voskhod launch vehicle. It carried the COSPAR identifier 1975‑041A and is catalogued in the Satellite Catalog Number (SCN) system as 07810.

## Key Facts  
- **Launch date:** 21 May 1975.  
- **Launch site:** Baikonur Cosmodrome, Site 31.  
- **Launch vehicle:** Voskhod rocket.  
- **Satellite type:** Zenit 2M optical reconnaissance (spy) satellite.  
- **COSPAR ID:** 1975‑041A.  
- **Satellite Catalog Number (SCN):** 07810.  
- **Aliases:** Kosmos 731.  
- **Instance of:** Zenit 2M, classified as an artificial satellite.  
- **Significant event recorded:** Rocket launch at 06:59:32 UTC on 21 May 1975 from Baikonur Site 31.  
- **Wikipedia language editions:** Hungarian, Macedonian, Serbo‑Croatian, Serbian.  

## FAQs  
### Q: What was the purpose of Cosmos 731?  
A: Cosmos 731 was an optical reconnaissance (spy) satellite built by the Soviet Union to gather photographic intelligence from orbit.  

### Q: Which launch vehicle placed Cosmos 731 into orbit?  
A: The satellite was launched aboard a Voskhod launch vehicle from Baikonur Cosmodrome’s Site 31.  

### Q: When and where was Cosmos 731 launched?  
A: It lifted off on 21 May 1975 at 06:59:32 UTC from Baikonur Cosmodrome, Kazakhstan, specifically from launch pad Site 31.  

### Q: What class of satellite does Cosmos 731 belong to?  
A: Cosmos 731 is an instance of the Zenit 2M class, a series of Soviet optical reconnaissance satellites.  

### Q: How is Cosmos 731 identified in international satellite registries?  
A: It carries the COSPAR designation 1975‑041A and the Satellite Catalog Number 07810.  

## Why It Matters  
Cosmos 731 represents a key element of the Soviet Union’s Cold‑War era reconnaissance architecture. As a Zenit 2M satellite, it contributed to the USSR’s ability to capture high‑resolution imagery of strategic targets worldwide, supporting military planning and verification of treaty compliance. The use of the Voskhod launch vehicle underscores the versatility of Soviet launch systems, which were employed for both crewed and uncrewed missions. By documenting its launch details, identifiers, and classification, Cosmos 731 helps historians and analysts trace the evolution of space‑based intelligence, assess technological capabilities of the period, and understand the broader context of satellite espionage that shaped international security dynamics. Its inclusion in multiple language Wikipedia editions and cataloging in global knowledge graphs ensures continued accessibility for research and public education.

## Notable For  
- Being a Zenit 2M optical reconnaissance satellite, part of a prolific Soviet spy‑satellite series.  
- Launching from Baikonur’s historic Site 31, a hub for many Soviet space missions.  
- Utilising the Voskhod launch vehicle, which also served crewed spacecraft missions.  
- Holding the COSPAR ID 1975‑041A and SCN 07810, making it traceable across international satellite databases.  
- Maintaining multilingual documentation (Hungarian, Macedonian, Serbo‑Croatian, Serbian) that reflects its global historical relevance.  

## Body  

### Overview  
Cosmos 731, also known as Kosmos 731, was an artificial satellite built by the Soviet Union for optical reconnaissance. It belongs to the Zenit 2M class, a line of spy satellites designed to capture photographic intelligence from low Earth orbit.

### Mission Profile  
- **Objective:** Acquire high‑resolution imagery of terrestrial targets for military and strategic analysis.  
- **Operational class:** Zenit 2M, indicating a specific generation of optical payloads and onboard systems.  

### Launch Details  
- **Date and time:** 21 May 1975, 06:59:32 UTC.  
- **Location:** Baikonur Cosmodrome, Kazakhstan, Site 31.  
- **Vehicle:** Voskhod rocket, a launch system employed for both crewed and uncrewed payloads.  
- **Event record:** Classified as a “rocket launch” significant event in satellite databases.  

### Satellite Identification  
- **COSPAR ID:** 1975‑041A, the international designator linking the launch year, launch sequence, and payload.  
- **Satellite Catalog Number (SCN):** 07810, used by tracking agencies to monitor objects in orbit.  
- **Aliases:** Kosmos 731, reflecting the common transliteration of the Russian “Космос”.  

### Classification and Relationships  
- **Instance of:** Zenit 2M, confirming its role as a reconnaissance platform.  
- **Broader class:** Artificial satellite, indicating it is a human‑made object placed in orbit.  
- **Related entities:** The Voskhod launch vehicle and the broader Zenit series of Soviet spy satellites.  

### Legacy and Documentation  
Cosmos 731 is referenced in multiple language editions of Wikipedia (Hungarian, Macedonian, Serbo‑Croatian, Serbian) and indexed in global knowledge graphs such as Google’s Knowledge Graph (ID /g/122vrfgc) and Wolfram Language (Entity["Satellite", "07810"]). These references preserve its technical details for future research and public knowledge.

## References

1. Jonathan's Space Report