One of the saddest aspects of city life is that we rarely think to look up at the sky. For one thing the city is always well lit up at night and we have no need of stars or moon. Indeed the cities of earth are all more visible from space than space is from them! We miss an awful lot, both by day and especially by night. Moreover the city is very busy; it’s the place of pavements, roads, buildings, noise, movement, speed and the place where a thousand and one things clamour for our attention. Our focus is below, not above; the sky is obliterated.