A telescope mirror that consists of several adjacent components which bring light to a common focus like one larger aperture. Typically the components are hexagonal in shape, and interlock like tiles. Each segment has a separate mounting with position sensors and actuators to maintain its alignment. Each of the two Keck Telescopes, for example, has 36 components 1.8 m across, forming a combined hexagonal aperture of 9.82 m. Segmented mirrors can be very light for their aperture, and can be made larger than individual mirrors.