# Cosmos 781
**Wikidata**: [Q12753997](https://www.wikidata.org/wiki/Q12753997)  
**Source**: https://4ort.xyz/entity/cosmos-781

## Summary
Cosmos 781 is a Soviet signals intelligence satellite launched on November 21, 1975. It is an instance of the Tselina-OK satellite class and was placed into orbit using a Kosmos-3M launch vehicle.

## Key Facts
- **Classification:** Tselina-OK model signals intelligence (SIGINT) satellite.
- **Launch Date:** November 21, 1975.
- **Launch Time:** 17:11:00 UTC.
- **Launch Vehicle:** Kosmos-3M rocket.
- **Launch Site:** Plesetsk Cosmodrome Site 132.
- **Country of Origin:** Soviet Union (USSR).
- **Satellite Catalog Number (SCN):** 08444.
- **COSPAR ID:** 1975-109A.
- **Aliases:** Kosmos 781.

## FAQs
### Q: What was the primary purpose of Cosmos 781?
A: Cosmos 781 was a Tselina-OK class satellite, which was a model of Soviet signals intelligence satellite. It was designed to conduct electronic reconnaissance from orbit.

### Q: When and where was Cosmos 781 launched?
A: The satellite was launched on November 21, 1975, at 17:11:00. The launch took place at Site 132 of the Plesetsk Cosmodrome.

### Q: What rocket was used to deploy Cosmos 781?
A: Cosmos 781 was launched using a Kosmos-3M rocket, a vehicle utilized for both Soviet and Russian space missions.

## Why It Matters
Cosmos 781 is a significant entry in the history of Soviet space exploration and military intelligence. As a Tselina-OK class satellite, it was part of a specialized fleet designed for signals intelligence (SIGINT). These satellites were critical for the Soviet Union's ability to monitor electronic signals from space, providing a strategic reconnaissance capability during the mid-1970s. The use of the Kosmos-3M rocket for its deployment demonstrates the specific utility of that launch vehicle for placing intelligence assets into targeted orbits.

Launched from the Plesetsk Cosmodrome Site 132, Cosmos 781 contributed to the operational density of the Soviet Union's orbital reconnaissance network. Its launch on November 21, 1975, marks a specific point in the technical progression of the Tselina-OK program. For researchers and space historians, Cosmos 781 serves as a verifiable data point in the study of 20th-century orbital surveillance. Its identification via SCN 08444 and COSPAR ID 1975-109A allows for precise tracking of its historical mission parameters within international satellite catalogs. By understanding the role of Cosmos 781, one gains insight into the scale and technical focus of Soviet signals intelligence efforts during this era.

## Notable For
- **Class Membership:** It is a documented instance of the Tselina-OK signals intelligence satellite series.
- **Specific Launch Origin:** Deployed from the high-latitude Plesetsk Cosmodrome at Site 132.
- **Standardized Identification:** Recognized in global tracking systems by SCN 08444 and COSPAR ID 1975-109A.
- **Historical Context:** Represents Soviet-era space technology launched during the year 1975.

## Body
### Technical Classification and Origin
Cosmos 781 (also referred to as Kosmos 781) is a satellite originating from the Soviet Union. It is classified as an instance of the Tselina-OK class. This specific model was developed as a signals intelligence satellite to gather electronic data from orbit.

### Launch and Orbital Deployment
The satellite was successfully launched on November 21, 1975. Key details of the launch event include:
- **Launch Time:** The event occurred at exactly 17:11:00.
- **Launch Vehicle:** The mission utilized the Kosmos-3M rocket, a launch vehicle associated with Soviet and Russian space programs.
- **Launch Site:** The rocket departed from Site 132 at the Plesetsk Cosmodrome.

### Identification and Cataloging
Cosmos 781 is tracked and identified through several international and technical designations:
- **SCN:** 08444
- **COSPAR ID:** 1975-109A
- **Wolfram Language Entity Code:** Entity["Satellite", "08444"]
- **Sitelink Count:** The entity is referenced across 3 different language versions of Wikipedia, including Macedonian (mk), Serbo-Croatian (sh), and Serbian (sr).

## References

1. Jonathan's Space Report