# SAMOS 4

> American reconnaissance satellite lost in a launch failure

**Wikidata**: [Q7410033](https://www.wikidata.org/wiki/Q7410033)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Samos_4)  
**Source**: https://4ort.xyz/entity/samos-4

## Summary  
SAMOS 4 was an American reconnaissance satellite that failed during launch on November 22, 1961. It was part of the early U.S. effort to gather intelligence via space-based surveillance. The mission was lost due to a rocket malfunction shortly after liftoff.

## Key Facts  
- Launched on November 22, 1961 at 20:45:47 UTC  
- Launch site: Vandenberg Space Launch Complex 3 West  
- Launch vehicle: Atlas-Agena B (serial number 108D/2202)  
- Instance of: reconnaissance satellite, former entity  
- Mission outcome: Lost due to launch failure  
- Preceded by: SAMOS 3  
- Followed by: SAMOS 5  
- Country of origin: United States  
- Alternate name: SAMOS E-5 No. 1  

## FAQs  
### Q: What happened to SAMOS 4?  
A: SAMOS 4 was lost during its launch on November 22, 1961, due to a failure of the Atlas-Agena B rocket. The mission did not achieve orbit and was considered a complete loss.

### Q: When was SAMOS 4 launched?  
A: SAMOS 4 was launched on November 22, 1961, at 20:45:47 UTC from Vandenberg Air Force Base in California.

### Q: What was the purpose of SAMOS 4?  
A: SAMOS 4 was designed as a reconnaissance satellite to collect intelligence data for the United States during the Cold War era.

## Why It Matters  
SAMOS 4 represents an early attempt by the United States to establish orbital reconnaissance capabilities during the height of the Cold War. Though unsuccessful, missions like SAMOS 4 contributed valuable lessons in spacecraft design, launch systems, and mission planning that informed later successful spy satellite programs such as Corona and Gambit. Its failure also highlights the high stakes and technical challenges inherent in early space-based intelligence operations.

## Notable For  
- One of the earliest dedicated reconnaissance satellites developed by the U.S.  
- Failed launch marked a setback in early national security space efforts  
- Part of the classified SAMOS program, which aimed to compete with Soviet surveillance advancements  
- Demonstrated the importance of reliable launch vehicles in covert space missions  

## Body  
### Mission Overview  
SAMOS 4 was intended to function as a photographic reconnaissance satellite under the broader SAMOS (Satellite and Missile Observation System) program. It was designed to capture imagery of foreign territories for intelligence purposes.

### Launch Details  
The satellite was launched atop an Atlas-Agena B rocket from Vandenberg Space Launch Complex 3 West. Liftoff occurred on November 22, 1961, at 20:45:47 UTC. Shortly after launch, the vehicle experienced a catastrophic failure, resulting in the total loss of the payload.

### Program Context  
SAMOS 4 followed the similarly failed SAMOS 3 and preceded SAMOS 5, both of which were part of the same experimental series. These missions underscored the difficulty of deploying operational reconnaissance platforms during the early 1960s.

### Technical Specifications  
While detailed technical documentation remains limited due to classification, SAMOS 4 was designated as SAMOS E-5 No. 1, indicating its role within the E-5 subsystem configuration used for certain imaging payloads.

### Legacy  
Despite its failure, SAMOS 4 contributed indirectly to the evolution of more robust and secure satellite reconnaissance technologies that became central to U.S. national defense strategy throughout the latter half of the 20th century.

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  "@type": "Thing",
  "name": "SAMOS 4",
  "description": "American reconnaissance satellite lost in a launch failure",
  "sameAs": [
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## References

1. Jonathan's Space Report