The Babylonian/Assyrian astrology later took hold in Egypt, Persia and other regions. Remnants of the Babylonian practice, such as the omens and settings of the planets and stars merged with Egyptian traditions. Scientists from both the nations made accurate measurements of areas using geometry and developed arithmetic in an algebraic direction. Mathematical astronomy was used to build multistory ziggurat tower.
Mesopotamian Astronomy and Astrology
The Egyptian contribution to astronomy/astrology was immense. The latter Hellenistic (Greek) astrologers of Egypt attribute the root of their discipline to Nechepso and Petosiris, an Egyptian pharaoh and his high priest. By the 1st century BC the entire apparatus of horoscopic astrology was in place and the language of Egyptian astrology had become Greek. The famed Greek astrologer, Valens traveled throughout Egypt and studied with at least a few living teachers of the old traditions and recorded his observations.
Originally the astrology texts were written in Coptic, the last form of ancient Egyptian, but no clear reference to any has survived. Over hundreds of years, the astronomers kept records and compiled archives of information about stars, planets and omens. The archives could be consulted by later astronomers to help them explain and interpret their own observations of the world around them.
Babylonian Astronomy History
Some of the oldest astronomical artifacts are astrolabe tablets. These clay tablets consisted of three concentric circles divided by twelve radii into twelve sections. Each of the thirty-six fields contained the names of constellations and simple numbers. No one yet understands the significance of these numbers.
It is believed that the numbers represented the months of the Babylonian calendar. These calendars are similar to calendars developed by the Egyptians. Astrolabes are still used today to determine the relative positions of stars and planets.
The sexagesimal numeral system was also used for temporal measurement: year was divided into 12 months, month into 30 days, day into 2x12 hours, hour into 60 minutes and minute into 60 seconds. The Mesopotamians also divided a circle into 360 degrees of 60 arc minutes.
The priests observed and recorded the celestial phenomena from the temples which also served as observatories. Both the Babylonians and the Assyrians were able to predict lunar eclipses. They applied a simple method which made future predictions based on past observations. Several cuneiform tablets list series of lunar eclipses and mark time between successive events.
We can see in the Sumerian calendar two concepts that were also followed by all later surrounding cultures:
use of the Moon to determine the length of a month (which began with the crescent first visible after a New Moon), and periodic adjustments to realign the lunar months with a solar calendar.