# STAR 25

> American solid-propellant rocket stage

**Wikidata**: [Q2840299](https://www.wikidata.org/wiki/Q2840299)  
**Source**: https://4ort.xyz/entity/star-25

## Summary
The STAR 25 is an American solid-propellant rocket stage manufactured by Thiokol. It is a member of the STAR and Altair families of rocket stages and is also known by the designations TE-M-184-3 and Altair 2. The stage was in service from 1963 to 1973.

## Key Facts
- **Classification:** American solid-propellant rocket stage (model).
- **Manufacturer:** Thiokol.
- **Also Known As:** TE-M-184-3, Altair 2.
- **Service Period:** Entered service in 1963; retired in 1973.
- **Power Plant:** Powered by the X-258 engine.
- **Lineage:** A subclass of the STAR and Altair rocket families.
- **Origin:** United States.

## FAQs
### Q: What is the STAR 25?
A: The STAR 25 is an American solid-propellant rocket stage developed by Thiokol. It served as an upper stage for rockets during its operational period from 1963 to 1973.

### Q: What engine or power source did the STAR 25 use?
A: The STAR 25 stage was powered by the X-258 engine system.

### Q: How is the STAR 25 related to the Altair rocket family?
A: The STAR 25 is classified as a subclass of the Altair family of American solid-propellant upper stages and carries the alias "Altair 2."

## Why It Matters
The STAR 25 represents a specific iteration of early American aerospace engineering focused on solid-propellant technology. Developed by Thiokol—a pioneer in rocket propulsion—this stage contributed to the modular approach of space launch logistics during the 1960s. As part of the broader STAR and Altair families, it exemplifies the era's reliance on solid fuel for upper-stage propulsion, offering reliability and storability compared to liquid alternatives. Its decade of service (1963–1973) coincides with a critical period of the Space Race and the expansion of satellite technology. While the specific missions utilizing the STAR 25 are defined by its role as an upper stage, its development underscores the industrial capability of the United States to produce specialized, inter-changeable rocket components during the height of the Cold War.

## Notable For
- **Family Integration:** Being a distinct model that bridges two major lineages: the STAR series and the Altair series of upper stages.
- **Specific Nomenclature:** Carrying the technical designation TE-M-184-3, indicating its specific engineering lineage within Thiokol's production catalog.
- **Historical Window:** Serving a precise ten-year window (1963–1973) that aligns with the transition from early spaceflight to more complex orbital delivery systems.

## Body

### Technical Design and Propulsion
The STAR 25 is defined as a solid-propellant rocket stage. Unlike liquid-fueled engines, this design utilizes solid propellant, which offers distinct advantages in terms of storage stability and mechanical simplicity. The stage was specifically powered by the X-258 motor, a designation that links it to a specific generation of propulsion technology used for orbital insertion or payload delivery.

### Manufacturer and Lineage
The stage was manufactured by Thiokol, a prominent American corporation responsible for many of the nation's rocket motors. The entity belongs to two significant classes of rocket hardware:
*   **STAR Family:** A broad family of American rocket stages developed by Thiokol, often used for upper-stage applications.
*   **Altair Family:** A specific class of American solid-propellant upper stages.

Due to this dual classification, the STAR 25 is also referred to as the **Altair 2**, signifying its position as an evolution or variant within that specific series.

### Operational History
The STAR 25 had a defined operational life within the United States space program. It officially entered service in **1963** and was retired a decade later in **1973**. Its existence as a "rocket model" suggests it was a production unit used across multiple missions rather than a one-off prototype, providing reliable upper-stage thrust during the Apollo era.