Muhammad ibn Abi Bakr al Ibari, Astrolabe with geared calendar

INTRODUCTION
- Man and the stars
SECTION I
- The dawn of astronomy: Mesopotamia, Egypt and the Biblical Cosmos
SECTION II
- The cosmos becomes a sphere
SECTION III
- The geometry of the cosmos
SECTION IV
- The skies of Islam
SECTION V
- Evangelisation of the cosmos
SECTION VI
- The Renaissance of Astronomy
SECTION VII
- Galileo: the cosmos through the telescope
SECTION VIII
- From Galileo to Newton

Sundial and pointer to the Mecca (qibla)

Gores of Ibrâhîm ibn Saîd al-Sahlî al-Wazzân’s celestial globe

Muhammad ibn Abi Bakr al Ibari, Astrolabe with geared calendar

Zoom

Muhammad ibn Abī Bakr al Ibarī (13th century)
Astrolabe with geared calendar, 1221-1222
Oxford, Museum of the History of Science, inv. 48213

This Persian astrolabe is the oldest complete device with cog wheels to have come down to us. On the front side it is an astrolabe, linked to the calendar by a gear train. On the back, the disc shows the phases of the Moon.