NSF / AURA / NSO Something New Under the Sun Entrance Aperture The carefully controlled dome opening is a key element in the safety control system. Primary Mirror This 4-meter mirror is the largest in the world for a solar telescope, enabling DKIST's super-highresolution images. Telescope Heat Stop This liquidcooled metal " doughnut " allows only a narrow beam of sunlight to pass through, eliminating more than 95% of the heat from the system. The optical and mechanical systems feed sunlight to the instrument lab below. Control Room Trained operators command the telescope and instruments from the safety of the control room. It is from here that the telescope is pointed. Coudé Laboratory This 150-ton rotating platform houses the scientific instruments and is where data are collected. The platform rotates to counteract the apparent rotation of the Sun in the sky. Support and Operations Building This building houses the control room, instrument-preparation lab, mechanicalequipment room, and other support spaces helpful to have near to hand. DKIST A slice through the Inouye Solar Telescope shows the observatory's main sections, from the telescope's mirrors near the top to the Coudé instrument lab below. The dome stands more than 43 meters (140 feet) tall, or roughly 10 stories. 16 NOVEMBER 2023 * SKY & TELESCOPE