A pair of deuterium-tritium Tokamak Fusion reactors.
In outer shape, the Hawking III can be described as a rectangular prism with a hemispherical dome on one of the larger faces. To each corner of the prism is then attached the cylindrically-shaped engines. This configuration of the Habitat is depicted in the works of Spacesim artist Chen-tao LaRochelle.
The interior of the Habitat is divided into three main decks: the Storage Deck, Habitation Deck, and Engineering Deck.
The Storage Deck is located in the dome structure on the Habitat, and contains tanks for gasses used in the Environmental Systems and for fuel. The Storage Deck is inaccessible from the Habitation Deck.
The Habitation Deck of the Hawking III is located inside the rectangular structure of the Habitat, and is divided into seven modules, each with its own bulkhead and environmental controls. These modules are the Airlock, the Bathroom, Command and Control, the Engineering Closet, the Hotlab, the Interlock, and the Longhouse. The Habitat Deck is accessible to the Astronauts.
The Engineering Deck is located in the rectangular structure of the Habitat below the Habitation Deck, and in inaccessible from the Habitation Deck. This deck contains the Reactor and Docking Clamps. All of the control systems for the systems in the Engineering Deck are located in the Habitation Deck, except for various manual shut-offs.