Why Are Our Skies So Dark? (Abstract)

Volume 23 number 2 (1995)

John Pazmino: New York, New York

Abstract

(Abstract only) Astronomers visiting New York note that it's a "dark" city. By this they mean that ourstreets and sky are not filled with the blazing lights so common in other towns across thecountry.Our cityscape is rather subdued for its huge population and uban vigor. The author showedsome of the structural features that inhibit the use of the typical town lighting schemes. Twoare highlighted: the fronts of stores and the skyscrapers. The former may be a model for othertowns, but the latter is pretty much unique to New York. Storefronts are built to cover andshield lamps from overhead view. Huge brilliant headsigns are banned. Many stores do quite well with essentially no outdoor lights at all. Other shops are built as interior spaces not open to the outside air. And virutally no shop has a carpark to light up.In New York City, a structure can combine residence, institutional, retail, commercial,corporate, and factory tenants. To accomodate this mulitple use the the structure extendsupward to nosebleed heights--literally scraping the sky when the clouds hang low. Thus within a hectar of less there can be tenants who in a rural setting could occupy a square kilometer of countryside. All that land and all those roads "must" be lit up. The skyscraper eliminates this "outside" and quenches the need or desire to install exterior illuminations. The entry lighting of a 150-m office tower with shops, a bank, and a school in it may handlily be outshined by astand-alone suburban bank. Densification of many facilities into a skyscraper also makes foreasy access among them. They are a short walk or elevator ride away, not many kilometers of driving in a star-killing car.New York City, with its peculiar structural features, has checked the rampant spread ofexcess and waste light emissions, rendering its skies about the darkest of any world city. In thissense, yes, New York is a dark city.