Home
Contents
Astro Index
 Previous
Big Bang
Activity
Astronomy

Astronomy, the physical study of the universe outside of the earth's atmosphere began during prehistoric times when man first gazed upon the stars. They developed stories as to what they were and how they came to be. These stories also entered into their religions and everyday life.

As man began to study the stars, he soon learned that the daily rotation of the stars was a means to tell time. The endless march of the moon through its phases and constellations was a convenient means to tell time and led to the development of calendars. The north star, located at the end of the handle of the constellation "Little Dipper", served as a means to navigate over land or sea.

The 6th Century B.C. Greeks viewed the earth as a motionless sphere in the center of a hollow globe, bounded by the universe. Here at the universe boundary were located the stars. This was the prevailing view of the universe until the 16th century when Copernicus changed the paradigm.

Before Copernicus's time, the world view was Ptolemaic. The earth was the center of the solar system and the sun and planets revolved around it. Copernicus proposed the theory that the sun was the centered of the solar system and the planets revolved around it. This view allowed for describing the rising and setting of the stars to the rotation of the earth. The stars slowly gained acceptance as remote suns at different distances from the earth. The path had been set for the development of the modern study of astronomy.

Click on the NASA earth image to learn more.   NASA changes these types of images everyday   in their Astronomy Picture of the Day program.
Home
Contents
Astro Index
 Previous
Big Bang
Activity