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Ptolemy was a great astronomer and mathematician. His astronomical theories and explanations however did not influence the study of the Sun for good but for evil. His wrong ideas dominated scientific thought until the 16th century.

Little is known of Ptolemy's early life. He was probably born in Greece, but nobody knows for sure. His real name, Claudius Ptolemaeus, tells us all that we know for certain about him. "Ptolemaeus" means he was a resident of Egypt, and "Claudius" signifies Roman citizenship. That is very confusing so most people assume he had dual-citizenship. Some sources say that he lived and worked in Alexandria, Egypt for most of his life.

Ptolemy's earliest and most famous work, was named "The Almagest". In this work, Ptolemy proposed the idea that accounted mathematically for the "motions of the planets, Sun, and moon against the un-moving stars". Ptolemy began the piece by saying that he accepted the generally believed theory that the earth did not move but was the center of the universe. According to him the planets and stars supposedly moved around the Earth in continuous perfectly round orbits. He then tried to explain why the planets at times appeared to travel backwards. He proposed that the planets, Sun, and moon moved in small circles around much larger circles in which the earth was centered. This theory had many holes in it but became generally accepted and it set back Sun research many centuries.

In the 16th century Nicolaus Copernicus rejected Ptolemy's system and developed his own "Earth is the center solar system" theory. His theory correctly stated that the Sun was located at the center of the solar system.

Ptolemy also advanced the study of trigonometry and wrote a world atlas called, "Ptolemy's Geography", which charts the world as it was commonly viewed during his time. Because of substantial errors his atlas set mankind back in its understanding of geography as well. Incorrect proportions and lack of reliable information influenced map makers for hundreds of years.

     

©Copyright 1998 Elizabeth Beckett, Holly Bernitt, and Vishwa Chandra.