# Delta J

> American expendable launch vehicle

**Wikidata**: [Q49545](https://www.wikidata.org/wiki/Q49545)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Delta_J)  
**Source**: https://4ort.xyz/entity/delta-j

## Summary
Delta J was an American expendable launch vehicle derived from the Delta E model. It served as a specific variant within the broader Thor-Delta family of rocket systems. The vehicle is notably associated with launching the NASA artificial satellite, Radio Astronomy Explorer A.

## Key Facts
*   **Classification:** Delta J is an expendable launch vehicle and a specific rocket model.
*   **Origin:** The vehicle is of United States origin.
*   **Parent System:** It is a subclass of the Thor-Delta American expendable launch system.
*   **Predecessor:** The design of the Delta J is based on the Delta E launch vehicle.
*   **Alternative Name:** The vehicle is also known by the alias "Thor-Delta J."
*   **Associated Payload:** It is related to the Radio Astronomy Explorer A, a NASA artificial satellite.
*   **Image:** A visual record of the Delta J is available via Wikimedia Commons.

## FAQs
### Q: What type of rocket was the Delta J?
A: The Delta J was an American expendable launch vehicle, meaning it was designed for one-time use. It is formally classified as a specific rocket model within the Thor-Delta family.

### Q: What was the Delta J based on?
A: The Delta J was based on the Delta E, another American expendable launch vehicle. It served as a further development or variant within this lineage.

### Q: What is the relationship between Delta J and Thor-Delta?
A: The Delta J is a subclass of the Thor-Delta launch system. While Thor-Delta is the broad class of the launch system, Delta J represents a specific model within that category.

## Why It Matters
The Delta J holds significance as a specialized iteration within the historic Thor-Delta rocket lineage, which was a cornerstone of American space launch capability. As an expendable launch vehicle based on the Delta E, it exemplifies the modular and evolutionary nature of early rocket science, where existing, reliable platforms were modified to meet specific mission profiles rather than designing entirely new vehicles from scratch.

Its existence highlights the adaptability of the Thor-Delta family to accommodate varying payload requirements. The vehicle is specifically relevant to the history of scientific space exploration due to its association with the Radio Astronomy Explorer A. By facilitating the deployment of such NASA artificial satellites, the Delta J contributed to the United States' efforts in space research and radio astronomy during the active era of the Thor-Delta program.

## Notable For
*   **Lineage:** Being a direct variant of the Delta E launch vehicle.
*   **Classification:** Existing as a distinct subclass of the widespread Thor-Delta launch system.
*   **Mission Utility:** Serving as the launch vehicle for the Radio Astronomy Explorer A satellite.
*   **National Origin:** Representing a component of the United States' aerospace engineering history.

## Body
### Design and Development
The Delta J is classified as a rocket model and an expendable launch vehicle. Developed in the United States, it is structurally and technically a subclass of the Thor-Delta launch system. The vehicle's design was not created in isolation but was explicitly based on the Delta E, an earlier American expendable launch vehicle. This lineage places the Delta J within one of the most enduring families of launch vehicles in space history.

### Nomenclature
The vehicle is officially designated as "Delta J" but is also recognized under the alias "Thor-Delta J." This naming convention reflects its heritage, linking the specific "J" variant to the broader "Thor-Delta" class identifier.

### Operational Role
The primary knowledge regarding the operational history of the Delta J links it to the deployment of specific orbital hardware. It is identified as the launch vehicle related to the "Radio Astronomy Explorer A," a NASA artificial satellite. This relationship underscores the vehicle's role in supporting scientific missions within the American space program. Visual documentation of the Delta J is maintained in the Wikimedia Commons category "Delta J."

## References

1. Freebase Data Dumps. 2013