Most studies of the Sun require observations over time. Thus a variety of monitoring stations have been set around the world to study solar phenomena on a variety of timescales. An important source of solar observations in the U.S. is the 150-foot "solar tower" telescope, located on Mount Wilson in California. This facility has been used on virtually every clear day for the last 23 years to study large and medium scale velocity and magnetic features on the surface of the Sun. In addition, its sister 90- foot tower is used daily to make sunspot drawings. These drawings are transmitted to the National Oceanic and Atmospheric Administration which make forecasts of solar flare events and assesses their impact on the Earth's magnetosphere. The Principal Investigator (PI) proposes to continue these observations over the next three years. During the new grant period a variety of large solar projects or spacecraft will be launched, such as the Solar Orbiting Helio-Observatory, the "MAX 91" solar-activity maximum campaign, and the Global Oscillation Network Group network, which will utilize solar oscillations to infer the interior rotation and density structure of the Sun. The Mt. Wilson observations will directly support these enterprises every clear day by providing an extensive, homogenous dataset of magnetic activity and gas flows on the solar surface.
