This year you can be green and dark at the same time by turning out, or at least down, the lights in your area. Bright or misdirected lights in your yard not only waste energy but they cause a type polliution called light pollution.

One fifth of the world's population cannot see the Milky Way because street lamps and building lights are too bright. So scientists are mounting a new campaign, called Dark Skies Awareness, aiming to reduce light pollution as part of the 2009 International Year of Astronomy

“Dark Skies Awareness” is one of 11 Global Cornerstone Projects during the 2009 International Year of Astronomy (IYA2009). Its goal is to raise the level of public knowledge about adverse impacts of excess artificial lighting on local environments and help more people appreciate the ongoing loss of a dark night sky for much of the world’s population. Toward this end, a range of programs and resource materials has been developed. Everyone is invited to use any of these as local solutions to a global problem.

The International Year of Astronomy 2009 (IYA2009) has been launched by the International Astronomical Union (IAU) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) under the theme, "The Universe, yours to discover". Thousands of IYA2009 events are described on the national websites, as well as on astronomy2009.org, and a few of the global projects are listed here.