# Kosmos 4

> first Soviet reconnaissance satellite

**Wikidata**: [Q53535](https://www.wikidata.org/wiki/Q53535)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Kosmos_4)  
**Source**: https://4ort.xyz/entity/kosmos-4

## Summary  
Kosmos 4 was the first Soviet reconnaissance satellite, launched in 1962 as part of the Zenit-2 program. It was designed for photographic surveillance and operated for three days before re-entering Earth's atmosphere.  

## Key Facts  
- **Launch Date**: April 26, 1962  
- **Mass**: 4,600 kilograms  
- **Orbital Parameters**: Apoapsis 330 km, periapsis 298 km, inclination 65°, orbital period 90.6 minutes  
- **Launch Vehicle**: Vostok-K rocket from Gagarin's Start  
- **Mission Duration**: Operated until April 29, 1962, when it re-entered the atmosphere  
- **Manufacturer**: S.P. Korolev Rocket and Space Corporation Energia  
- **COSPAR ID**: 1962-014A  
- **Class**: Zenit-2 reconnaissance satellite  
- **Aliases**: Also known as Cosmos 4  

## FAQs  
### Q: What was the purpose of Kosmos 4?  
A: Kosmos 4 was the first Soviet reconnaissance satellite, designed for photographic surveillance during the Cold War.  

### Q: How long did Kosmos 4 stay in orbit?  
A: It operated for three days, from April 26 to April 29, 1962, before re-entering Earth's atmosphere.  

### Q: What rocket launched Kosmos 4?  
A: It was launched aboard a Vostok-K rocket from Gagarin's Start, a Soviet launch site.  

## Why It Matters  
Kosmos 4 marked a significant milestone in Soviet space technology, demonstrating the USSR's capability to conduct orbital reconnaissance during the Cold War. As the first successful reconnaissance satellite in the Zenit-2 program, it paved the way for future Soviet spy satellites, which played a critical role in military intelligence. Its short but successful mission validated key technologies for photographic surveillance from space, influencing later satellite designs and Cold War strategic planning.  

## Notable For  
- **First Soviet reconnaissance satellite**  
- **Part of the Zenit-2 program**, a classified military surveillance initiative  
- **Launched aboard a Vostok-K rocket**, a variant of the Vostok family used for human spaceflight  
- **Operated for only three days**, typical of early reconnaissance missions  

## Body  
### Mission Overview  
- Kosmos 4 was launched on April 26, 1962, as part of the Zenit-2 program.  
- Its primary objective was photographic reconnaissance for military intelligence.  

### Technical Specifications  
- **Mass**: 4,600 kg  
- **Orbit**: Near-circular with an apoapsis of 330 km and periapsis of 298 km  
- **Inclination**: 65°  
- **Orbital Period**: 90.6 minutes  
- **Eccentricity**: 0.002394  

### Launch and Re-Entry  
- **Launch Site**: Gagarin's Start  
- **Launch Vehicle**: Vostok-K rocket  
- **Re-Entry**: April 29, 1962, after three days in orbit  

### Legacy  
- Demonstrated Soviet capability in space-based reconnaissance.  
- Set the foundation for subsequent Zenit-2 missions.

## References

1. Jonathan's Space Report
2. Freebase Data Dumps. 2013