Egyptian astronomy
[citation needed] Astronomy played a considerable part in fixing the dates of religious festivals and determining the hours of night, and temple astrologers were especially adept at watching the stars and observing the conjunctions and risings of the Sun, Moon, and planets, as well as the lunar phases.
In 1006, Ali ibn Ridwan observed the SN 1006, a supernova regarded as the brightest stellar event in recorded history, and left the most detailed description of it.
In the 14th century, Najm al-Din al-Misri wrote a treatise describing over 100 different types of scientific and astronomical instruments, many of which he invented himself.
The annual flooding of the Nile meant that the heliacal risings, or first visible appearances of stars at dawn, were of special interest in determining when this might occur.
[2] The precise orientation of the Egyptian pyramids serves as a lasting demonstration of the high degree of technical skill attained in the 3rd millennium BCE.
Astronomy played a considerable part in religious matters for fixing the dates of festivals and determining the hours of the night.
The rising of Sirius (Egyptian: Sopdet, Greek: Sothis) at the beginning of the inundation was a particularly important point to fix in the yearly calendar.
[7] Beginning with the 9th Dynasty, ancient Egyptians produced 'Diagonal star tables', which were usually painted on the inside surface of wooden coffin lids.
According to the texts, in founding or rebuilding temples the north axis was determined by the same apparatus, and we may conclude that it was the usual one for astronomical observations.
They have been identified with two inscribed objects in the Berlin Museum; a short handle from which a plumb line was hung, and a palm branch with a sight-slit in the broader end.
[citation needed] Ibn Yunus (c. 950–1009) observed more than 10,000 entries for the Sun's position for many years using a large astrolabe with a diameter of nearly 1.4 meters.
He says that the object was two to three times as large as the disc of Venus and about one-quarter the brightness of the Moon, and that the star was low on the southern horizon.
[16]: 333 In 14th century Egypt, Najm al-Din al-Misri (c. 1325) wrote a treatise describing over 100 different types of scientific and astronomical instruments, many of which he invented himself.
