Marseille Observatory is an astronomical observatory located in Marseille, France. In its incarnation in 1877, it was the discovery site of a group of galaxies known as Stephan's Quintet, discovered by its director Edouard Stephan. A reflecting telescope is an optical telescope invented in the 17th century which uses a single or combination of curved mirrors that reflect light and form an image, as an alternative to the refracting telescope which, at that time, suffered from severe chromatic aberration. Reflecting telescopes may employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Despite the theoretical advantages of the reflector design, the difficulty of construction and the poor performance of the speculum metal mirrors being used at the time meant it took over 100 years for them to become popular. | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Science Source |
Taille de l’image : | 2955 px × 4650 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |