title: Time to turn off the lights.
authors.affiliation: Cerro Tololo Inter-American Observatory, Casilla 603, La Serena, Chile. msmith@ctio.noao.edu
authors.forename: Malcolm
authors.initials: M
authors.lastname: Smith
mesh_terms: D025041:Animal Migration / Q000528:radiation effects; D000818:Animals; D001256:Astronomy / Q000639:trends; D003246:Conservation of Energy Resources / Q000191:economics / Q000639:trends; D003624:Darkness; D004787:Environmental Pollution / Q000009:adverse effects* / Q000191:economics / Q000517:prevention & control*; D004867:Equipment Design / Q000639:trends; D006801:Humans; D008029:Lighting / Q000009:adverse effects* / Q000191:economics