# Cosmos 840
**Wikidata**: [Q12754024](https://www.wikidata.org/wiki/Q12754024)  
**Source**: https://4ort.xyz/entity/cosmos-840

## Summary
Cosmos 840 was a Soviet spy satellite launched in 1976 as part of the Zenit 2M reconnaissance program. It was launched aboard a Soyuz-U rocket from the Plesetsk Cosmodrome and operated under the Kosmos designation, a cover name for Soviet military satellites.

## Key Facts
- **Launch Date**: July 14, 1976  
- **COSPAR ID**: 1976-068A  
- **Launch Vehicle**: Soyuz-U rocket  
- **Launch Site**: Plesetsk Cosmodrome, Site 43/4  
- **Satellite Class**: Zenit 2M (Soviet reconnaissance satellite)  
- **Alternative Name**: Kosmos 840  
- **Significant Event**: Rocket launch at 09:00:00 UTC on July 14, 1976  
- **SCN (Satellite Catalog Number)**: 09019  

## FAQs
### Q: What type of satellite was Cosmos 840?  
A: Cosmos 840 was a Zenit 2M-class satellite, a Soviet military reconnaissance spacecraft used for photographic intelligence.  

### Q: When and where was Cosmos 840 launched?  
A: It was launched on July 14, 1976, from Plesetsk Cosmodrome Site 43/4 aboard a Soyuz-U rocket.  

### Q: What was the purpose of Cosmos 840?  
A: As part of the Zenit 2M program, its primary mission was high-resolution photographic surveillance for Soviet military intelligence.  

## Why It Matters  
Cosmos 840 was part of the Zenit 2M series, a key component of the Soviet Union's Cold War-era reconnaissance efforts. These satellites provided critical imagery intelligence, aiding military and strategic decision-making. The Zenit 2M series improved upon earlier models with enhanced camera systems and longer operational lifespans. The use of the Soyuz-U rocket, a reliable workhorse of Soviet spaceflight, underscored the program's importance. While not publicly acknowledged at the time, such missions laid the groundwork for modern satellite reconnaissance.  

## Notable For  
- **Military Reconnaissance**: Operated as a classified spy satellite under the Kosmos designation.  
- **Zenit 2M Class**: Featured advanced imaging capabilities compared to earlier Zenit models.  
- **Soyuz-U Launch**: Demonstrated the reliability of the Soyuz-U rocket for military payloads.  

## Body  
### Launch Details  
- **Date**: July 14, 1976  
- **Time**: 09:00:00 UTC  
- **Site**: Plesetsk Cosmodrome Site 43/4 (a primary launch facility for Soviet military satellites).  

### Satellite Specifications  
- **Class**: Zenit 2M (improved variant of the Zenit reconnaissance series).  
- **Designation**: Publicly labeled "Cosmos 840" to conceal its military purpose.  

### Mission Context  
- **Primary Role**: High-resolution photographic surveillance.  
- **Operational Lifespan**: Typical Zenit 2M missions lasted 10-30 days before film return.  

### Launch Vehicle  
- **Rocket**: Soyuz-U, a derivative of the Soyuz family optimized for reliability.  
- **Payload Capacity**: Capable of delivering ~6,000 kg to low Earth orbit.

## References

1. Jonathan's Space Report