The largest Schmidt telescope, the 48-inch (122-centimeter) diameter Oschin Telescope, is at Palomar Observatory on Mount Palomar, California. It was used between the years 1952 and 1959 to conduct the Palomar Optical Sky Survey, the first major systematic photographic survey of the entire northern (and part of the southern) sky. Since then, the survey has been updated using digital camera technology. The telescope has also been used to search for distant Kuiper Belt and Oort Cloud objects. The Oschin Telescope was used to discover many of the largest known Kuiper Belt Objects, such as Varuna, Quaoar, and 2003 UB 313 (which is even larger than Pluto), and also Sedna, thought to be the first Oort Cloud object ever discovered.