Astronomer Biography- Johann Bayer

Johann Bayer and His Contributions to Astronomy

     Johann Bayer was a German lawyer and uranographer- also known as a celestial cartographer. Bayer was born on an unknown date in the year 1572, in Rain, Lower Bavaria. As a young adult, he studied philosophy and law at the University of Ingolstadt. Upon completion of his studies, he moved to Augsburg to practice law. Here he became legal advisor to the city council in 1612. Bayer was also interested in other subjects, such as archaeology and mathematics. However, he is mainly known for his work in astronomy and for determining the position of many objects in the celestial sphere.

            Bayer is undoubtedly most recognized for a book he published, a star atlas by the name of Uranometria Omnium Asterismorum, or Uraniometry of all the Asterisms. This work was first published in Augsburg in 1603, and was the first atlas that covered the entirety of the celestial sphere. This book was based upon the works of Tycho Brahe, a fellow astronomer, and also incorporated some of the ideas of Alessandro Piccolomini’s star atlas of 1540. However, Bayer included an additional 1,000 stars. Bayer’s atlas added 12 new constellations, previously unknown to the Greeks and the Romans, which occupied the Southern night sky. The Uranometria also introduced a new system of star designation, appropriately named Bayer Designation.

            The Bayer Designation System is a stellar designation in which a certain star is identified by a Greek letter, followed by the genitive form of its parent constellation’s Latin name. The original list of Bayer Designations contained 1,564 stars. Most of the stars which are brighter were given their first names by Bayer in Uranometria. Bayer designated a lower case Greek letter, such as alpha (α), followed by the Latin name of the parent constellation. For example, α Tauri, pronounced alpha Tauri. As the Greek alphabet only has 24 letters, Bayer began to use uppercase letters, allowing for an additional 24 letters. Bayer designations, while they have been improvised, are still being used to this day. This designation system remains as one of the greatest contributions of Bayer to modern astronomy, along with his Uranometria. The crater Bayer, located in the Southwest section of the moon is named after the great German astronomer.

            On the 7^th of March, 1625, at the age of 53, Johann Bayer died in the city of Augsburg. Although his death seemed to be at a relatively early age by today’s standards, it was an average life expectancy for the 16^th-17^th centuries. Bayer left behind a legacy after his death, his extremely innovative Uranometria depicted numerous stars and constellations that were previously unnamed, and his Bayer Designation System, used for designating stars in constellations, is still used today. Bayer was a very successful man, a prolific lawyer, and of course, an extremely talented astronomer. The works of Bayer and his astronomical findings proved to be extremely influential to modern day astronomy, are still being used in modern-day astronomy, and will be used for generations to come.