Great Surveys of the Universe

Looking ahead to the next decade and imagining the landscape of astronomy in 2020, it is clear that astronomical surveys, large and small, plus extensive follow-up projects, will be a great engine of progress in our profession. Surveys have long had a critical role in astronomy, and in the coming decades will be even more central as we probe deeper into the Universe. In fact, one might call the next two decades the "Era of Great Surveys". This next generation of surveys will probe a huge range of astronomical objects and phenomena including planets, stars, gas, galaxies, background radiation, dark matter, dark energy, degenerate matter compact objects, black holes, magnetic fields, cosmic ray particles, neutrinos, gravity waves, and exotica (particles, topological defects, etc.). This Position Paper advocates the overarching theme of a true Survey of the Universe built up of a diverse range of "great surveys" and the exploitation of these surveys. A significant number of the proposed decadal activities and facilities are either explicitly Survey Telescopes or plan to devote significant amounts of time to survey science. Others, such as large aperture narrow field telescopes, are aimed at targeted detailed observations that are a necessary counterpoint or follow-up to surveys. To discuss overarching issues such as this, the Great Surveys of Astronomy Workshop was held 20-22 November 2008 in Santa Fe, NM and was sponsored by the LANL Institute for Advanced Study and AUI.