The Orb was the tenet system of an extinct sentient race that lived on Bion. Given the name, it is possible that the "Orb" refers to an orb or other object of great importance. It may or may not represent a spherical artifact recovered during M02: Hardball in Metroid Prime: Federation Force, that was the source of a mysterious signal on Bion. General Alex Miles later states that this artifact was highly sought after by a Galactic Federation research team, and that it dates back to before the inhabitants of Bion went extinct. It was broadcasting a distress signal, which would only receive a response when it was too late.
In the briefing for M05: Excavation, Miles reveals that the team has made some discoveries with the artifact. It was paired with a data codex, which the Pirates stole. The artifact contained a detailed map of Bion that showed the rescue site the ancient race had intended to use, at which a backup copy of the codex could be found.