Kitt Peak National Observatory, astronomical observatory located southwest of Tucson, Ariz.; it was founded in 1958 under contract with the National Science Foundation and is administered by the Association of Universities for Research in Astronomy. Its principal instrument is the Mayall 158-in. (4-m) reflector. The observatory's equipment also includes 84-in. (2.1 m), 50-in. (1.3-m), 36-in. (0.9-m), and 16-in. (0.4-m) reflecting telescopes as well as a planned 3.5-m telescope. Used for wide angle photographs and electronic images of the sky, the Burrell Schmidt telescope is operated jointly with Case Western Reserve Univ. The 60-in. (1.5-m) Robert McMath Solar Telescope is the largest instrument of its kind in the world. Stellar research, now part of the National Optical Astronomy Observatories, includes basic research on galaxies, stars, nebulae, and the solar system. The solar division, now part of the National Solar Observatory, using the solar telescope in coordination with a vacuum spectrograph, analyzes the composition, magnetic field strength, motion, and physical nature of the sun. Other telescopes are located on Kitt Peak, notably those of the National Radio Astronomy Observatory and Steward Observatory. Any astronomer can apply for time on the telescopes. A telescope allocation committee of astronomers selects the best proposals and time is assigned every six months.