Heaven's Gate is a planet orbiting the star Vega Prime  and part of the WorldWeb during the Web Era. Originally it was a miserable world of boiling mud, pestilent swamps, and unbreathable atmosphere. It was bombarded with blazing radiation from its sun Vega Prime. 
However, the Hegemony of Man had terraformed it to shade trees and comfort. Its Promenade gardens were a famous attraction of the capital Mudflat City. Its terraforming depended on an orbital containment sphere and atmosphere-generating stations that took centuries to be built. 
During its prime, it had a population of 400 million people. 
During the Pax Era, its population was reduced to less than a dozen mineral prospectors and an orbital Pax garrison that rarely ventured into the ruined world.