# Cosmos 639
**Wikidata**: [Q12753933](https://www.wikidata.org/wiki/Q12753933)  
**Source**: https://4ort.xyz/entity/cosmos-639

## Summary
Cosmos 639 was a Soviet satellite launched on April 4, 1974, designated within the broader Cosmos program. Classified as a Zenit-4MK spacecraft, it was deployed into orbit using a Voskhod launch vehicle from the Plesetsk Cosmodrome.

## Key Facts
*   **Entity Type:** Zenit-4MK (satellite class).
*   **Launch Date:** April 4, 1974.
*   **COSPAR ID:** 1974-019A.
*   **Launch Site:** Plesetsk Cosmodrome Site 41.
*   **Launch Vehicle:** Voskhod.
*   **Significant Event:** Rocket launch occurring at 08:30:00 on April 4, 1974.
*   **Alternate Name:** Kosmos 639.
*   **Satellite Catalog Number (SCN):** 07240.

## FAQs
### Q: What type of spacecraft was Cosmos 639?
A: Cosmos 639 was an instance of the Zenit-4MK class of satellites.

### Q: When and where was Cosmos 639 launched?
A: It was launched on April 4, 1974, at 08:30:00 from the Plesetsk Cosmodrome Site 41.

### Q: What launch vehicle was used to deploy Cosmos 639?
A: The satellite was launched using a Voskhod rocket.

## Why It Matters
Cosmos 639 represents a specific mission within the extensive Soviet Cosmos program, serving as a notable example of the Zenit-4MK satellite configuration. Launched in the mid-1970s, this mission highlights the operational tempo and technological deployment strategies of the Soviet Union during this era of space exploration. By utilizing the Voskhod launch vehicle—a system derived from the R-7 rocket family often used for both crewed and uncrewed missions—this entity illustrates the intersection of launch infrastructure and reconnaissance or scientific satellite deployment. The precise tracking of its launch time (08:30:00) and location (Site 41) provides valuable data for historians and analysts studying the launch cadence and site utilization of the Plesetsk Cosmodrome during the Cold War.

## Notable For
*   **Classification:** Identified specifically as a Zenit-4MK, distinguishing it from other satellite models in the Cosmos series.
*   **Launch Precision:** Recorded with a precise launch time of 08:30:00.
*   **Site Specificity:** Launched from Plesetsk Cosmodrome Site 41, a specific operational pad within the complex.
*   **Nomenclature:** Serves as a case study for the Soviet "Cosmos" designation policy, which obscured the specific nature of military or experimental satellites under a generic name.

## Body

### Mission Profile and Classification
Cosmos 639 was a man-made object launched under the Soviet Cosmos program, a designation used for a wide variety of Soviet satellites. Structured data confirms that Cosmos 639 was an instance of the **Zenit-4MK** class. This classification links the entity to a specific lineage of Soviet hardware designed for orbital operations.

### Launch Logistics
The mission originated from the **Plesetsk Cosmodrome**, specifically **Site 41**. The launch took place on **April 4, 1974**. The "significant event" associated with this entity is cataloged as a rocket launch, with a precise timestamp of **08:30:00**.

The launch vehicle responsible for placing Cosmos 639 into orbit was the **Voskhod**. In the context of this entity, Voskhod refers to the launch vehicle class (a derivative of the R-7 Semyorka), though the name also designates a series of Soviet crewed spacecraft.

### Identification and Aliases
The satellite is identified internationally by the **COSPAR ID 1974-019A** and the Satellite Catalog Number (SCN) **07240**. It is also referred to by the alias **Kosmos 639**. The entity has sitelinks in multiple languages, including Macedonian (mk), Serbo-Croatian (sh), and Serbian (sr), indicating its documentation across various regional knowledge bases.

## References

1. Jonathan's Space Report