Ibn al-Shatir
He found through observation that the Sonnenapogäum not migrated exactly with the rate of precession (namely with 1 ° per 60 Persian years compared to 1 ° per 70 Persian years ), with respect to the fixed stars, so moving independently (see Apsidendrehung ).
Ibn al- Schatir stood in the tradition of Maragha school. He improved the system of Claudius Ptolemy, by dissolving the need for an equant in his treatise Kitab al- Nihayat Sulfi tashih al - Usul. Of equant was in the epicycle an auxiliary construction, which is the apparent center of the uniform circular motion, but not coincident with the center of the circular path or to the position of the earth. He introduced an extra epicycle, which the Ptolemaic system ( in the same way as later Nicolaus Copernicus) differed. He introduced so that a mathematically similar modifications such as Copernicus, though he remained in the geocentric system itself. It has therefore been suggested that Ibn al- Schatir Copernicus influenced.
1371/1372 he constructed a large sundial for the Umayyad Mosque in Damascus. In 1371 he introduced the division of the day in the whole year same hours.
See also:
- Heliocentric world picture
- Georg von Peuerbach and John Engel for possible transmission routes to Nicolaus Copernicus
Writings
- Talic al - Arsad. (Observations, lost? )
- Kitab al - sul fi nihayat tashih al - usul.
- Al- Zij al - Jadid. (New astronomical handbook)