An astronomer with his astrolabe,an illustration from the Nuernberg Chronicles of the World,published in 1493. The astrolabe was a primitive type of instrument used,in the form shown here,to measure the altitudes of stars (their angular heights above the horizon). The altitude of a standard star could be used to determine the time of night | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Burgess, Dr. Jeremy |
Taille de l’image : | 3821 px × 4667 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |