Years ago I read a Poul Anderson story titled 'To Build a World' involving terraforming Earth's Moon. With only 1/6th Earth's gravity the Moon will not permanently hold a breathable atmosphere but 'permanent' is relative and Poul (who always did his homework) assumed a useable life of about 50,000 years for a breathable Lunar atmosphere - well worth our bother. I don't remember how Poul's progagonists generated their Lunar atmosphere but in My Universe we are collecting raw materials by de-orbiting ice chunks from Saturn's ring system - a formidable task but once underway, a steady string of man-made 'comets' plunge into the inner solar system, carefully jockied into orbit in a temporary artificial ring system around Luna before being transferred to the surface. In this view, riding a conglomerate heap of ice boulders and 'snow', we are approaching the Earth/Moon system with the ringed Moon in the foreground, the Earth in the distance. Dust and gasses subliming from the imported ice already in orbit enshroud the Moon in a huge, temporary 'comet', a spectacular sight visible throughout the entire solar system. Solar radiation likewise makes a 'mini-comet' of the snowball we are riding but so tenuous that seen from the inside it is all but invisible. I really just wanted an excuse to fiddle with the play of sunlight penetrating fractured ice boulders along the 'horizon' of the 'snowball'. I'm not sure that really shows up in this low-quality scan. Shown approx. 50% larger than the original. Original: 3'x5' pencil.