The Agena launch vehicle is my version of a commercial rocket akin to the real-world SpaceX Falcon 9. The Agena Upper Stage is is powered by a single Charger engine that burns RP-1 and LOX. The stage is designed with low-boil-off technology and solar panels, giving it considerable on-orbit endurance. It can be used as a propulsion and power module for a larger spacecraft such as the Agena Freighter and Agena Tanker. It also serves as the propulsion module for the Mk II Gemini spacecraft. Fully reusable, the Agena Upper Stage deploys an inflatable heat shield and it steers towards its landing zone via a parafoil. Just before landing, the stage inflates an airbag; the AUS land at White Sands in New Mexico, or at the Dugway Proving Grounds in Utah. Given its low cost and reusability, the US Air Force in my fictional universe has a small fleet of Agena launch vehicles that they maintain, which is why you see this one painted in Air Force markings.