Category:O'Neill-class

The O'Neill-class space station were the most common space station design constructed by United Earth, save for the hollowed asteroid design space colonies.

Technical Data
Consisting of a rotating cylinder, 8-kilometers in diameter, and capable of scaling up to 32-kilometers long. The cylinder had six equal-area stripes that ran the length of the cylinder; three are transparent windows, three are habitable "land" surfaces. Furthermore, an outer agricultural ring, 16-kilometers in radius, rotates at a different speed to support farming.

Farming
The habitat's industrial manufacturing block is located in the middle, to allow for minimized gravity for some manufacturing processes.

Construction
To save the immense cost of rocketing the materials from Earth, these habitats would be built with materials launched into space from the Luna via magnetic mass driver.

Artificial Gravity
The cylinders rotate to provide artificial gravity on their inner surface. Due to their very large radii, the habitats had to rotate only about forty times an hour to simulate a standard Earth-gravity. Almost no-one would experience motion sickness due to coriolis forces acting on the inner ear. People would be able to detect spinward and anti-spinward directions by turning their heads, and any dropped items would appear to be deflected by a few centimeters. The central axis of the habitat would be a zero-gravity region, and it was envisaged that recreational facilities could be located there.

Atmosphere & Radiation
The habitats were pressurized with oxygen at partial pressures roughly similar to terrestrial air, 20% of the Earth's sea-level air pressure. Nitrogen would was also included to add a further 30% of the Earth's pressure. This half-pressure atmosphere would save gas and reduce the needed strength and thickness of the habitat walls.

At this scale, the air within the cylinder and the shell of the cylinder provided adequate shielding against cosmic rays. The internal volume of an O'Neill cylinder was great enough to support its own small weather systems, which could be manipulated by altering the internal atmospheric composition or the amount of reflected sunlight.

Sunlight
Large mirrors were hinged at the back of each stripe of window. The unhinged edge of the windows pointed toward the nearest stellar body. The purpose of the mirrors was to reflect sunlight into the cylinders through the windows. Night was simulated by opening the mirrors, letting the window view empty space; this also permits heat to radiate to space. During the day, the reflected star-light would appear to move as the mirrors move, creating a natural progression of "Sun" angles. Although not visible to the naked eye, the Sun's image would be observed to rotate due to the cylinder's rotation. The light reflected from the mirrors was polarized, at times confused pollinating bees.

To permit light to enter the habitat, large windows ran the length of the cylinder. These were not a single pane, but rather were made up of many small sections, to prevent catastrophic damage, and so the aluminum or steel window frames could take most of the stresses of the air pressure of the habitat. Occasionally a meteorite would break one of these panes. This would cause some loss of the atmosphere, but would not be an emergency, due to the very large volume of the habitat.

Crew
An O'Neill-class space station could support up to 25,000,000 residence in relative comfort and be considered largely self-sustaining. It only required a crew of around 35,000 to maintain and operate its support facilities.

Armaments
The station carried no true armaments beyond point-defense systems. However its port and dock facilities could support numerous patrol ships, allowing for launch and maintain sizable patrols of fighters up to frigates. With proper modifications they could support crafts of almost any size, including dreadnoughts.