# Kosmos 901

> Soviet anti-ballistic missile radar target

**Wikidata**: [Q53638](https://www.wikidata.org/wiki/Q53638)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Kosmos_901)  
**Source**: https://4ort.xyz/entity/kosmos-901

## Summary
Kosmos 901 was a Soviet anti-ballistic missile (ABM) radar target satellite launched in 1977. It was an instance of the DS-P1-I class, a specialized model of Soviet satellite designed specifically for radar calibration and testing.

## Key Facts
- **Launch Date:** April 5, 1977 (10:30:00)
- **Classification:** DS-P1-I radar calibration satellite
- **Primary Function:** Soviet anti-ballistic missile radar target
- **Manufacturer:** Pivdenne Design Office
- **Launch Vehicle:** Kosmos-2I carrier rocket
- **Launch Site:** Plesetsk Cosmodrome Site 133
- **Satellite Catalog Number (SCN):** 09905
- **COSPAR ID:** 1977-025A
- **Country of Origin:** Soviet Union

## FAQs
### Q: What was the primary purpose of Kosmos 901?
A: Kosmos 901 served as a radar target for Soviet anti-ballistic missile systems. It was part of the DS-P1-I series, which provided ground-based radar stations with a consistent target for calibration and performance testing.

### Q: When and where was Kosmos 901 launched?
A: The satellite was launched on April 5, 1977, from Site 133 at the Plesetsk Cosmodrome. The launch occurred at 10:30:00 UTC using a Kosmos-2I rocket.

### Q: Who built Kosmos 901?
A: Kosmos 901 was manufactured by the Pivdenne Design Office. It was deployed as part of the Soviet Union's military space infrastructure.

### Q: What rocket was used to launch Kosmos 901?
A: It was launched using the Kosmos-2I, a Soviet carrier rocket that has since been superseded.

## Why It Matters
Kosmos 901 was a critical component of the Soviet Union's military space program, specifically within the realm of anti-ballistic missile (ABM) defense. As a DS-P1-I class satellite, it functioned as a dedicated radar target, a role essential for the calibration and operational readiness of ground-based radar networks. These networks were responsible for detecting and tracking potential missile threats, and satellites like Kosmos 901 allowed for the precise tuning of these sensors. 

The satellite's manufacture by the Pivdenne Design Office and its launch from the Plesetsk Cosmodrome highlight the coordinated effort of Soviet aerospace engineering and military strategy during the late 1970s. By providing a reliable, space-based target, Kosmos 901 helped ensure the accuracy of the Soviet Union's early warning systems. Its deployment via the Kosmos-2I rocket underscores the technical infrastructure required to maintain a sophisticated defense posture during the Cold War. Ultimately, Kosmos 901 represents the intersection of orbital technology and national security, serving as a necessary tool for the validation of complex radar systems.

## Notable For
- **Specialized Class:** It is a member of the DS-P1-I class, a specific lineage of satellites dedicated to radar calibration.
- **Cold War Defense:** Acted as a functional target for the Soviet Union's anti-ballistic missile radar systems.
- **Pivdenne Design:** Manufactured by the Pivdenne Design Office, a major contributor to Soviet aerospace history.
- **Plesetsk Launch:** Deployed from the high-latitude Plesetsk Cosmodrome Site 133.

## Body
### Mission and Classification
Kosmos 901 was an artificial satellite identified as an instance of the DS-P1-I class. This model was developed by the Soviet Union to serve as a radar calibration satellite. Its primary mission was to act as a target for anti-ballistic missile (ABM) radar systems, facilitating the testing and refinement of Soviet defense sensors.

### Launch Details
The satellite was launched on April 5, 1977, at exactly 10:30:00. The mission originated from Site 133 at the Plesetsk Cosmodrome. The launch vehicle utilized for this mission was the Kosmos-2I, a Soviet carrier rocket that has since been superseded.

### Technical Specifications and Identification
- **Manufacturer:** Pivdenne Design Office
- **Satellite Catalog Number (SCN):** 09905
- **COSPAR ID:** 1977-025A
- **Freebase ID:** /m/064n1g1
- **Wolfram Language Code:** Entity["Satellite", "09905"]

### Related Systems
Kosmos 901 is closely associated with the DS-P1-I satellite series and the Kosmos-2I rocket. The Kosmos-2I was a Soviet Union carrier rocket used for deploying various military and scientific payloads during this era. The DS-P1-I class itself is a recognized model of radar calibration satellites with a sitelink count of 3, while the Kosmos-2I rocket has a sitelink count of 10.

## References

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