Changes

Astronomy helped form both lunar and solar-based calendars, where ancient societies even understood that the solar year was slightly more than 365 days. Navigation of ship-borne trade before 1000 BCE was mostly confined to areas along the coast or regions that can more easily observe land. However, astronomy made it possible to navigate in open waters and during the night. Whereas early navigation depended on land features, understanding the position of stars allowed the Phoenicians and Greeks to colonize wide areas of the Mediterranean Sea in the 1st millennium BCE, spreading their cultures in wide areas. Babylon and wider Babylonia were one of the key regions for many ancient developments. This included the development of the zodiac signs, still utilized today, and even a coordinate system to identify the positioning of stars and constellations. A system for predicting eclipses was even developed, invented in Babylon, which is still utilized, called the Solaris system. The coordinate system developed was the eventual 60-based system we use to describe global navigation today.<ref>For more on calendars and observations of eclipses, see: Lawson, R. M. (2004). <i>Science in the ancient world: an encyclopedia.</i> Santa Barbara, Calif: ABC-CLIO, pg. 32.</ref>

[[File:Astrolabe-Persian-18C.jpg|thumbnail|left|300px|Figure 2. Astrolabe from Persia.]]

In the Middle East and Asia, astronomy had developed and retained knowledge from ancient periods to allow the development of accurate calendars and to make accurate predictions in the movement of celestial bodies. Astrolabes and other navigation equipment became commonly used to assist in observing the positioning of stars to inform sailors of their relative position, where such technologies derived from earlier, ancient observations (Figure 2). However, after the fall of Rome, astronomy had made limited or few advancements in Western Europe <ref>For more on navigation and star positioning, see: Denny, M. (2012). <i>The science of navigation: from dead reckoning to GPS.</i> Baltimore: John Hopkins University Press.</ref>