Tag: Moon

Ibn al-Zarqalluh’s discovery of the annual equation of the Moon

by S. Mohammad Mozaffari Published on: 9th February 2024

Ibn al-Zarqālluh (al-Andalus, d. 1100) introduced a new inequality in the longitudinal motion of the Moon into Ptolemy’s lunar model with the amplitude of 24′, which periodically changes in terms of a sine function with…