# Thor-Agena D

> American orbital launch vehicle

**Wikidata**: [Q9358558](https://www.wikidata.org/wiki/Q9358558)  
**Source**: https://4ort.xyz/entity/thor-agena-d

## Summary
The Thor-Agena D was an American orbital launch vehicle, part of the Thor-Agena family, used to deploy a wide range of satellites, including reconnaissance, scientific, and military payloads. It consisted of a PGM-17 Thor first stage and an RM-81 Agena second stage, manufactured by Douglas, and played a key role in U.S. space missions during the 1960s.

## Key Facts
- **Classification**: American orbital launch vehicle, subclass of the Thor-Agena family.
- **Manufacturer**: Douglas.
- **Components**: PGM-17 Thor (first stage), RM-81 Agena (second stage).
- **Country of Origin**: United States.
- **Related Vehicles**: Thorad-Agena D (a more powerful variant).
- **Notable Payloads**:
  - Reconnaissance satellites: Corona series (e.g., Corona 48, 58, 60, 62, 69, 85, 88, 96, 98, 110, 112), KH-4 series (e.g., KH-4 9033, 9038, 9044, 9045, 9049, 9054, 9056, 9057, 9061, 9062), KH-4A series (e.g., KH-4A 1002, 1004, 1005, 1006, 1007, 1008, 1009, 1011, 1012, 1015, 1016, 1017, 1018, 1019, 1021, 1022, 1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031, 1033), KH-5 series (e.g., KH-5 9065A, 9066A), KH-6 series (e.g., KH-6 8002, 8003).
  - Scientific satellites: OGO 2, OGO 4 (geophysical research), PAGEOS (passive geodetic satellite), RADOSE (1963), GGSE-1 (experimental), GGSE 2, GGSE 3, Injun 3 (geophysical research), STARAD (radiation monitoring), SOLRAD 7B, Solrad 6, Solrad 7A (solar monitoring).
  - Military satellites: SECOR 1, SECOR 3 (geodetic), Hitchhiker 1 (US Air Force), OPS 3762 (reconnaissance), Poppy 1A, Poppy 1B, Poppy 3A (spy satellites), Ferret 4, Ferret 6, Ferret 8 (signals intelligence), Pundit 1 (electronic intelligence), GRAB 6.
  - Other payloads: Multi Research Payload Vehicle (military research, lost in launch failure), OSCAR 3 (amateur radio), Calsphere 1A, Dodecahedron, SURCAL 1A, SURCAL 1B, SURCAL 2B, LOFTI 2A, P35-6, P35-7, P35-9, 1964-031A, LAMPO, ORBIS LOW.
- **Launch Failures**: Corona 60 (reconnaissance satellite lost in launch failure).
- **Image**: Available at [Wikimedia Commons](https://commons.wikimedia.org/wiki/Special:FilePath/Poppy-1_launch_on_Thor_Agena-D_at_Vandenberg_AFB_1962.jpg).
- **Wikidata Description**: "American orbital launch vehicle."
- **Encyclopaedia Britannica ID**: Topic "Thrust-Augmented Thor."

## FAQs
**What was the Thor-Agena D?**
The Thor-Agena D was an American orbital launch vehicle used primarily in the 1960s to deploy satellites for reconnaissance, scientific research, and military purposes. It was part of the Thor-Agena family and consisted of a Thor first stage and an Agena second stage.

**What satellites did the Thor-Agena D launch?**
It launched a diverse array of satellites, including the Corona and KH-4/KH-4A reconnaissance series, scientific satellites like OGO 2 and OGO 4, military satellites such as SECOR and Poppy, and experimental payloads like GGSE-1 and OSCAR 3.

**Who manufactured the Thor-Agena D?**
The Thor-Agena D was manufactured by Douglas, an American aerospace company.

**What was the Thorad-Agena D?**
The Thorad-Agena D was a more powerful variant of the Thor-Agena D, also developed by the USA for launching heavier payloads.

**Were there any notable launch failures involving the Thor-Agena D?**
Yes, the Multi Research Payload Vehicle and Corona 60 were lost in launch failures involving the Thor-Agena D.

## Why It Matters
The Thor-Agena D was a critical launch vehicle during the early years of the U.S. space program, enabling the deployment of satellites that advanced scientific research, military reconnaissance, and geodetic studies. Its role in launching the Corona spy satellites provided the U.S. with vital intelligence during the Cold War, while scientific missions like OGO 2 and OGO 4 expanded our understanding of Earth's geophysical properties. The vehicle's reliability and versatility made it a cornerstone of American space operations in the 1960s, supporting both civilian and military objectives.

## Notable For
- **Versatility**: Launched a wide range of payloads, from reconnaissance and scientific satellites to military and experimental missions.
- **Cold War Contributions**: Played a key role in deploying Corona spy satellites, which were essential for U.S. intelligence gathering.
- **Scientific Advancements**: Supported geophysical research missions like OGO 2 and OGO 4, as well as solar monitoring satellites like SOLRAD 7B.
- **Military Applications**: Launched geodetic satellites (SECOR), signals intelligence satellites (Ferret series), and other military payloads.
- **Launch Failures**: Notable for the loss of the Multi Research Payload Vehicle and Corona 60, highlighting the risks of early spaceflight.
- **Manufacturing**: Produced by Douglas, a major aerospace contractor of the era.

## Body
### Overview
The Thor-Agena D was an American orbital launch vehicle designed for deploying satellites into low Earth orbit. It was part of the broader Thor-Agena family, which included variants like the more powerful Thorad-Agena D. The vehicle consisted of two stages: the PGM-17 Thor as the first stage and the RM-81 Agena as the second stage. Manufactured by Douglas, the Thor-Agena D was a workhorse for the U.S. space program during the 1960s, supporting both civilian and military missions.

### Technical Specifications
- **Stages**: Two-stage rocket (Thor first stage, Agena second stage).
- **Manufacturer**: Douglas.
- **Country of Origin**: United States.
- **Payload Capacity**: Designed to launch a variety of satellites, including reconnaissance, scientific, and military payloads.

### Launch History and Payloads
The Thor-Agena D was responsible for launching numerous satellites, including:
- **Reconnaissance Satellites**:
  - **Corona Series**: Corona 48, 58, 60 (lost in launch failure), 62, 69, 72, 85, 88, 96, 98, 110, 112.
  - **KH-4 Series**: KH-4 9033, 9038, 9044, 9045, 9049, 9054, 9056, 9057, 9061, 9062.
  - **KH-4A Series**: KH-4A 1002, 1004, 1005, 1006, 1007, 1008, 1009, 1011, 1012, 1015, 1016, 1017, 1018, 1019, 1021, 1022, 1024, 1025, 1026, 1027, 1028, 1029, 1030, 1031, 1033.
  - **KH-5 Series**: KH-5 9065A, 9066A.
  - **KH-6 Series**: KH-6 8002, 8003.
- **Scientific Satellites**:
  - **OGO Series**: OGO 2, OGO 4 (geophysical research).
  - **PAGEOS**: Passive geodetic satellite launched by NASA in 1966.
  - **RADOSE**: Satellite launched in 1963.
  - **GGSE Series**: GGSE-1 (experimental), GGSE 2, GGSE 3.
  - **Injun 3**: Geophysical research satellite.
  - **STARAD**: Radiation-monitoring satellite.
  - **SOLRAD Series**: SOLRAD 7B, Solrad 6, Solrad 7A (solar monitoring).
- **Military Satellites**:
  - **SECOR Series**: SECOR 1, SECOR 3 (geodetic satellites).
  - **Hitchhiker 1**: US Air Force satellite.
  - **OPS 3762**: Reconnaissance satellite launched in 1964.
  - **Poppy Series**: Poppy 1A, Poppy 1B, Poppy 3A (spy satellites).
  - **Ferret Series**: Ferret 4, Ferret 6, Ferret 8 (signals intelligence).
  - **Pundit 1**: Electronic and signal intelligence satellite.
  - **GRAB 6**: Signals intelligence satellite.
- **Other Payloads**:
  - **Multi Research Payload Vehicle**: Military research satellite destroyed in a launch failure.
  - **OSCAR 3**: Amateur radio satellite.
  - **Calsphere 1A**, **Dodecahedron**, **SURCAL 1A**, **SURCAL 1B**, **SURCAL 2B**, **LOFTI 2A**, **P35-6**, **P35-7**, **P35-9**, **1964-031A**, **LAMPO**, **ORBIS LOW**.

### Related Vehicles
- **Thor-Agena**: The broader class of American orbital launch vehicles to which the Thor-Agena D belongs.
- **Thorad-Agena D**: A more powerful variant of the Thor-Agena D, developed by the USA for launching heavier payloads.

### Legacy and Impact
The Thor-Agena D was instrumental in advancing U.S. capabilities in space during the 1960s. Its ability to launch diverse payloads made it a versatile tool for both scientific and military applications. The vehicle's contributions to reconnaissance missions, such as the Corona program, provided critical intelligence during the Cold War. Additionally, its role in launching scientific satellites helped expand knowledge in geophysics, solar research, and radiation monitoring. Despite some launch failures, the Thor-Agena D remains a significant part of the history of American spaceflight.