Advanced Technology Solar Telescope

High-resolution studies of the Sun’s magnetic fields are needed for a better understanding of the fundamental processes responsible for solar variability. The generation of magnetic fields through dynamo processes, the amplification of fields through the interaction with plasma flows, and the destruction of fields are poorly understood. There is incomplete insight into physical mechanisms responsible for chromospheric and coronal structure and heating, causes of variations in the radiative output of the Sun, and mechanisms that trigger flares and coronal mass ejections. Progress in answering these critical questions requires study of the interaction of the magnetic field and convection with a resolution sufficient to observe scale fundamental to these processes. The planned 4 m aperture ATST will be a unique scientific tool, with excellent angular resolution, a large wavelength range, and low scattered light. With its integrated adaptive optics, the ATST will achieve a spatial resolution nearly 10 times better than any existing solar telescope. The ATST design and development phase began in 2001 and it is now ready to begin construction in 2009.