The Kottamia Observatory and Other Aspects of Astronomy in Egypt

Extract

The 74-inch (1.8m) telescope of Kottamia Observatory is the largest telescope in North Africa and the Middle East. It stands on a plateau 485m above sea-level and 70km to the east of Cairo. The latitude is 25^° 55’.9 N and the longitude 31^° 49’.5E. The telescope is of conventional type, having Newtonian (f/4.9), Cassegrain (f/18) and coudí (f/28.9) foci; it was built by Grubb-Parsons (U.K.). The main mirror is of Duran 50 glass, and has a clear aperture of 74 inches (1.8m) and a focal length, for its paraboloidal surface, of 360 inches (9.2m). The secondary mirrors are of fused quartz. The telescope is provided with a Newtonian camera, a single-channel photoelectric photometer, a Cassegrain spectrograph comprising two cameras with dispersions of 100 Amm⁻¹ and 48 Amm⁻¹ at 4800A and a coude spectrograph with two cameras allowing dispersions of 20Amm⁻¹ and 6Amm⁻¹. A four-component correcting lens has been supplied to be mounted at the Newtonian focus, in order to reduce the effect of coma on photographic observations.