Sector B-042 is a sector of interstellar space situated in UNSC territory. It is a desolate, empty region of space, where no one would expect to find a ship. This makes it well-suited for clandestine meetings or complicated ship repairs.
In October 2531, the UNSC Point of No Return was in sector B-042 so that a high level secret meeting between high-ranking officers of the Office of Naval Intelligence could take place aboard. The result of that meeting was the creation of Colonel James Ackerson's SPARTAN-III Program.