A Strategy for Urban Astronomical Observatory Site Preservation: The Southern Arizona Example

摘要

Urbanized observatories are under financial pressures for numerous and complex reasons, including concerns that increasing sky brightness will continue to erode their scientific viability. The history of urbanized observatories is one of steady decline and divestiture. We argue that light at night (LAN) impacts of urban growth are inadequately understood, that current measurement techniques are incomplete in scope, and that both limit the effectiveness of mitigation programs. We give examples of these factors for Pima County, Arizona, and propose techniques and a program that could provide focus and power to mitigation efforts, and could extend the longevity of southern Arizona observatories.