Arithmetic or astronomy, an old science, which is known to man, the nations of Egypt, Mesopotamia, Babylon and China, sejab 20th century BC have known and studied astronomy this. known as astrology. According to the history, the division sepeken (week) over seven days, the presence dating back more than 5000 years ago
In the early part of its history, astronomy only observation and forecast movement of objects in the sky that can be seen with the naked eye. Then around the 12th century BC, and our country, astronomy has undergone many advances. they have been able to calculate when the occurrence of eclipses, and count the stars appeasement.