Ptolemy, Astronomy and Almagest

The Ancient Greek Ptolemaic Geocentric Astronomical System Ptolemy’s geocentric astronomical system placed Earth at the center of the universe and he was considered the ultimate...

Ptolemy and Geography

The Ancient Greek Ptolemaic Geographical System Ptolemy’s geography contained many errors, but it also pioneered many concepts that we still use today. Ptolemy Ptolemy¬†(aka Claudius...

Ptolemaic Geocentric Astronomy

Ptolemy’s Geometric Devices Deferent, Epicycle, Eccentric, & Equant Ptolemy’s geocentric astronomical system used four geometric devices, the deferent, epicycle, eccentric, and equant, to explain the...