The Oort Cloud is a sphere of dust and asteroids that extends to the edge of the gravitational reach of the sun. The difficulties of life without infrastructure in the Kuiper Belt are compounded in the Oort Cloud. Because of this, the transhuman population in the Oort Cloud is less than 15,000, almost all restricted to a handful of ships and research outposts within the Inner Oort Cloud.
The Inner Oort Cloud, from 2,000 to 5,000 AU, marks the outermost expansion of transhumanity. Several millions of asteroids are documented, ranging from a few meters to 2,000 kilometers across. Resources include ice, organics, minerals, and, due to heavy exposure to cosmic wind, a number of rare elements including lithium and boron, though commercial mining is unfeasible.
The Outer Oort Cloud extends to 150,000 AU from the sun to interstellar space. The Outer Oort Cloud has been the subject of significant scienti c scrutiny as the frontier for astronomy, physics, and spaceflight. Only three pre-Fall probes have breached the area; it otherwise remains beyond the reach of transhumanity. The Outer Oort Cloud is scanned by hundreds of thousands of professional and amateur telescopes, watching for the return of the TITANs or the arrival of Factor lighthuggers.