A Digital Computer as Process Controller of a 2.2 m Ritchey-Chrétien Telescope

Abstract

In 1969 a new astronomical institution was founded in the Federal Republicof Germany. This “Max-Planck-Institut für Astronomie” will consist of a central institute at Heidelberg and two observatories, one in the South-East of Spain and one in the Southern hemisphere (possibly in South-West Africa). Each observatory will be equipped with a 2.2-metre Ritchey-Chrétien telescope; these instruments are now under construction at Carl Zeiss, Oberkochen, Western Germany. In addition, a 3.5-metre telescope will be built. A smaller Ritchey-Chrétien telescope of 1.2 m will go into operation next year in Spain. The mirror disks of the 3.5-metre and 2.2-metre telescopes have been ordered from Schott & Gen. at Mainz; they are made of glass ceramic “Zerodur”, a zero-expansion material similar to CerVit. In the operation of the 2.2-metre telescopes and their peripherals, small, general purpose digital computers will be employed.