History of the telescope a wider field of view than a classic Cassegrain. During the period 1850–1900, reflectors suffered from problems with speculum metal mirrors, and a considerable number of "Great Refractors" were built from 60 cm to 1 metre aperture, culminating in the Yerkes Observatory refractor in 1897; however, starting from the early 1900s a series of ever-larger reflectors with glass mirrors were built, including the Mount Wilson 60-inch (1.5 metre), the 100-inch (2.5 metre) Hooker Telescope (1917) and the 200-inch (5 metre) Hale telescope (1948); essentially all major research telescopes since 1900 have been reflectors. A number of 4-metre class (160 inch)
Aristarchos 2.3 m Telescope Aristarchos 2.3 m Telescope The New Greek Telescope project of the National Observatory of Athens (NOA) was funded by the European Commission and the General Secretariat for Research and Technology of the Hellenic Ministry of Development. The telescope had its first light test in 2005, and became the largest telescope in Greece when it became fully operational at the Chelmos Observatory site in 2007. The telescope has a Ritchey-Chrétien configuration with a primary mirror with a diameter of 2.3 m. The mount is of the altazimuth kind. The telescope is operated by the Institute for Astronomy, Astrophysics, Space Applications and