History of the telescope
The earliest known telescope appeared in 1608 in the Netherlands when an eyeglass maker named Hans Lippershey tried to obtain a patent on one. Although Lippershey did not receive his patent, news of the new invention soon spread across Europe. The design of these early refracting telescopes consisted of a convex objective lens and a concave eyepiece. Galileo improved on this design the following year and applied it to astronomy. In 1611, Johannes Kepler described how a far more useful telescope could be made with a convex objective lens and a convex eyepiece lens and by 1655 astronomers such as Christiaan Huygens were building powerful but unwieldy Keplerian telescopes with compound eyepieces.
La Silla Observatory
By 1976, the largest telescope planned, the , started operations. It was subsequently to have a 1.4m CAT (Coudé Auxiliary Telescope) attached. In 1984, the 2.2m telescope began operations, while in March 1989, the 3.5 m New Technology Telescope (NTT) saw first light. The program reached its apex with the installation of the SEST in 1987 (Swedish ESO Submillimetre Telescope), the only large submillimetre telescope in the southern hemisphere, which was a combined project between ESO and the Swedish Natural Science Research Council. Around the end of the century some of the original telescopes were closed: the 1m Schmidt closed in 1998 and the 1.5m in 2002, while new equipment owned by various foreign observatories was introduced. A 1-metre telescope owned by Marseille Observatory opened in 1998, followed by a 1.2-metre telescope from Geneva Observatory in 2000.