Installation 03

Installation 03, also known as Gamma Halo to humanity, is one of the seven massive Halo fortress worlds built by the Forerunners. It is also the third Halo installation to be discovered by Humanity. Installation 03 is located in the Khaphrae system, and was managed by its Monitor, 049 Abject Testament. According to Cortana, it is also where the found the coordinates to Requiem.

Summary
The purpose of Installation 03, along with its brethren, was to preclude and thwart the parasite forms known as the Flood from consuming all sentient life in the galaxy. In the event of a Flood outbreak, one of the seven installations could be triggered to annihilate all sentient life within 25,000 light years. Once one ring is set off all remaining rings would activate. All seven rings could be fired at once if need be.

Very little is known about this installation, and it has yet to be directly observed, though it appears to have a red and cracked surface, indicating vast deserts and what appears to be volcanic activity. (Such volcanic activity, if present, would have to be artificially induced as the Halo rings lack the tectonic movement necessary for natural volcanic activity.)

History
During the Battle of Installation 05 in 2552, a signal was sent to this Halo from Installation 05, putting it on standby mode. A readout from Installation 05's Control Room showed that Installation 03 was fully prepared to fire on demand.

A more comprehensive readout was later observed on the Ark during the Battle of Installation 00 by the Arbiter, John-117, and the High Prophet of Truth. John-117 deactivated the installation before it could be fired.

Shortly before March 2553, Installation 03 began to be researched and monitored by the UNSC Ivanoff Research Station. During this time Marine and SPARTAN-IV teams trained on the ring's surface.

Before the Halo rings were fired, the Librarian hid the Composer away from the Ur-Didact on Installation 03 to prevent him from digitizing the rest of the human race into ancillae for his Promethean warframes. It was recovered from the ring by the and taken to the Ivanoff research station prior to 2557, a process which Dr. Sandra Tillson claimed took 3 months to complete.

In addition to the Composer, the Ivanoff Research Station was also home to Installation 03's Activation Index. After the station's attack and desiccation by the Covenant Remnant and the Ur-Didact, it is unknown what became of the ring and its Index.

Trivia

 * It appears to have a Venusian surface. It is likely that images of Venus' surface were transposed onto the ring's hologram for Halo 3.
 * This ring is often mistaken for Installation 05 because of the order the rings appear in The Covenant. Although it is not so, because Installation 05 is the fifth ring from the platform on which Truth and the Brutes reside rather than the direction in which the player enters the area, whereas the fifth ring in from the entrance has an apparently volcanic surface. In-game data files confirm this fact.
 * Unlike Installations 04 and 05, which orbit large gas giants, Installation 03 orbits a rocky planet, whose face has been shattered as a result of a fairly recent impact event; the debris from the impact, still aglow as of 2557, has collected to form a dense asteroid field in orbit over the planet as well as Installation 03. though it is possible that this is just a moon and the gas giant hasn't been seen.
 * The numbering of the rings concerning the IWHBYD ring sequence is the opposite to the rings' actual installation numbers.
 * Like all Halo Arrays, Installation 03 derives its power from the Power Rooms which are connected to other Power Rooms placed around the whole ring.
 * Defender-class SPARTAN-IVs were originally stationed on the ring at some point before or during 2557.
 * When seen from space, large circles of light are visible on the dark side of ring, indicating there are Forerunner cities or perhaps large UNSC bases on the interior surface.
 * Installation 03 is the first Halo Installation seen in the series that is not attempted to be activated on-sight. It is, however, attempted to be activated from Installation 00 during the events of Halo 3.
 * It is quite possible there is a Flood research facility on this ring just like the majority of the Installations, but has yet to be found/opened. It is also possible the Flood may return later in the Reclaimer Trilogy.
 * Both Installation 03 and Installation 06 share the term Gamma Halo so it is not exactly known what 06 would be.

List of Appearances

 * Halo 2
 * Halo 3
 * Halo Legends
 * Origins
 * Halo: Glasslands
 * Halo 4