What Is Reach?

Reach is the name given to the planet Epsilon Eridani II, one of several worlds in a stellar system 10.5 light years from Earth. One of the Inner Colonies of Earth’s unified government, Reach was considered a sister planet to Earth itself, both for its relative proximity to humanity’s crucible and for its eventual establishment as not just a major colony world—one of the most populated worlds in the colonies—but also the command headquarters of Earth’s military, the United Nations Space Command.
As it is in the Halo show, where it appeared during season one, Reach was home to not just the UNSC’s military command, as well as vital shipyards developing the fleet’s capital ships, but also home to two of its intelligence agency ONI’s biggest projects: the Spartan-II program and the accompanying MJLONIR armor project. It saw 75 children from across Earth’s colonies abducted and trained to become an elite class of genetically enhanced super soldiers designed to fight humanity’s perceived greatest threat—growing insurrections in the outer colony worlds, seeking freedom from Earth’s direct rule. One such child, of course, was John, designated 117, who would go on to become the legendary Master Chief.