Medieval Astronomy - even in the Dark Ages people studied the stars

You may have heard the term Medieval astronomy and think there was no such thing. Who could blame you, because the Medieval period is also called the Dark Ages. Most people think that this means there was no art, mathematics, or science at all. However, while learning in the medieval period was heavily restricted by the Church, there was still scientific discovery going on.

Astronomy in the Dark ages

People in the Middle Ages cared about astronomy for a number of reasons. Religion was one of the most important. Medieval astronomy was used to figure out when holy days would occur, such as Easter. This holiday was particularly hard to place on the calendar every year. This is because the original date of Easter was determined by Passover, a Jewish holiday. The Jewish calendar is based on a lunar, or moon cycle. The medieval calendar, however, was based on the movement of the sun. Therefore, observation of the sky was needed to figure out when this very important holiday would occur.

The Sun and the Moon

Medieval astronomy was based on four main kinds of celestial bodies. The first was the Sun. The Sun was the most important object in the sky. At the time, people thought that it went around the Earth. However, they still needed to watch it to figure out how long the year was and when certain times, like planting, should happen. The second most important body in the sky was the Moon. Its phases were used to determine holy days and other important events. It, too, was thought to go around the earth.

The stars came next in importance. It was not known that the sun is a star in the Medieval period. Instead, the stars were considered to be fixed lights in the sky. Medieval people were aware of all of the constellations we recognize in the Northern Hemisphere today. Most medieval astronomers used Aristotle's vision of the sky, which was made up of concentric crystal spheres. The planets, stars, and other bodies were each held in their own sphere. Thomas Aquinas, an early Church philosopher, blended this idea with those of Ptolemy to come up with the astronomy recognized by the church for hundreds of years.

Last, but not least - the planets

Last in importance were the planets. Not all of the planets we recognize today had been discovered by Medieval astronomy. They were not aware of the existence of Uranus and Pluto. It is important to remember that to medieval astronomers, the planets were only visible as lights, not as the objects we think of them as today. Towards the end of the medieval period, many astronomers began to make changes to the official science approved by the Church. These took the form of comments about Aristotle's theories. As long as the comments ended by saying that Aristotle was correct, no one paid much attention to changes in the theories.

A final word

Although Medieval astronomy was restricted by the Church, it still understood a lot about the stars and planets. Most people in the medieval period still believed that the Earth was the center of the universe. However, astronomers were able to observe the movements of the stars and sun in relation to the Earth and chart them down. It was irregularity in these movements that eventually caused people to believe that the Earth went around the sun, not the other way around.

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