Oort cloud
From Tardis Wiki, the free Doctor Who reference
The Oort cloud was a region on the edge of the Solar system filled with asteroids. (PROSE: To the Slaughter)
Many comets originated there. An alien probe searching for signs of life used it as a base of operations. (AUDIO: Murmurs of Earth) By the 24th century, it had become a navigational hazard. To fix that and improve the system's feng shui, Robart Falsh and Aristotle Halcyon sold all the asteroids in the cloud to the Kilomons, Draconians and other alien races.. (PROSE: To the Slaughter)
