Here is a very brief background on UNSC Dawn Under Heaven. It is subject to change. PLEASE note that this is completely made up. With all known data, there still is nothing to base anything from. UNSC Dawn Under Heaven has only been mentioned ONCE by Jason Jones in an interview in 2001 as the sister ship of the Pillar of Autumn.

Built in 2509, UNSC Dawn Under Heaven and Pillar of Autumn were two of the toughest vessels in the United Nations Spaces Command fleet. As Halcyon-class cruisers, they lacked fire power and speed but were tough as nails. With hulls over 2 meters thick, it would be incredibly hard to penetrate.

Headed for scrap by the turn of the century, UNSC Pillar of Autumn was pardoned and retrofitted for the Human-Covenant War. Home of the SPARTAN-II, UNSC Pillar of Autumn was a force not to be reckoned with. Unfortunately, UNSC Dawn Under Heaven did not receive the pardon its crew wished for. In 2542, the ship was technically decommissioned and scraped. Stories circulated that pieces of Heaven were implemented into the Autumn.

Those stories are false. Instead of being sent to its final resting place, Reach Station Gama, by authority of ONI: Sector Zero UNSC Dawn Under Heaven arrived at a top secret facility. There, like its sister the Autumn, it was retrofitted to new specifications, including a prototype stealth system. UNSC Dawn Under Heaven would become center of some other UNSC best kept secrets.

Housing an Elite Reconnaissance and Special Operations team, ERSO, UNSC Dawn Under Heaven was ONI's eyes and ears of reconnaissance, thus creating the code "Heaven is watching." Before nearly all recorded engagements or conflicts involving the UNSC, ground side or space, UNSC Dawn Under Heaven provided valuable intelligence that turned the tides.

After the first contact UNSC Dawn Under Heaven was reassigned to penetrate Covenant-controlled space to provide intelligence. After Reach fell, the Dawn went MIA, loosing all communication with ONI and the UNSC.