The Solar Year Calculated
بِسۡمِ ٱللهِ ٱلرَّحۡمَـٰنِ ٱلرَّحِيمِ
In the early 900s, Imam Abu ‘Abdullah Muhammad ibn Jabir ibn Sinan ar-Raqqi al-Battani (r.a.) calculated a solar year as being 365 days, 5 hours, 46 minutes and 24 seconds. The length of the average solar year, at the equinoctial, is 365 days, 5 hours, 48 minutes and 45 seconds. That is an impressive feat.