In the 16th century, Denmark was larger than it is at present. Its territory extended to Knudstrup in southern Sweden, where Tycho Brahe was born. So Tycho was a subject of the Danish crown.
Tycho’s star rose as other luminaries were sinking beneath life’s horizon. Tycho saw the light of day in 1546, the same year that Martin Luther died. Other historical figures left the earthly scene a little later. Henry VIII, King of England, died in 1457; and Francis I, king of France, passed away in the same year as his English rival.
For three years, Tycho studied law at the University of Copenhagen. He then spent time at various German universities, including Rostock, where he lost part of his nose in a duel.
Law did not appeal to Tycho. He became interested in celestial phenomena, and developed into an astronomer.
The late 16th century was a good time to gaze heavenward. In 1572 a supernova appeared in the constellation Cassiopeia, and in 1577 a brilliant comet startled the world. Tycho examined both of these celestial phenomena with meticulous care.
Because of his published work on the supernova, it has been called “Tycho’s star.” It was traditionally believed that the heavens were unchangeable. Tycho refuted this belief by demonstrating that the supernova was truly a celestial phenomenon.
In his studies of the comet, he refuted a persistent misconception that had held sway since the days of Aristotle. Aristotle had taught that comets resided in the earth’s atmosphere, but Tycho correctly concluded that they streaked across the sky in outer space.
Frederick II, the king of Denmark, decided to patronize his illustrious subject. He placed the island of Hven at the astronomer’s disposal. Tycho settled here in 1576 and built an observatory called Uraniborg.
Even before he had come to Hven, Tycho noticed errors in current star tables and began to make corrections. He continued this work at Uraniborg, and developed more accurate star tables. He also made accurate observations concerning planetary movements. He accomplished this work without the help of any telescope, which Hans Lippershey invented in 1608, seven years after Tycho’s death.
In 1588 King Frederick II died. Tycho’s relations with Christian IV, the new Danish king, were not cordial. The astronomer eventually left his beloved observatory.
He found a new patron in Rudolph II, emperor of the Holy Roman Empire. As a result, Tycho took up residence in Prague, where Rudolph II lived.
His work in Prague was cut short by death in 1601; but before he died, he brought Johannes Kepler to Prague and gave him valuable assistance. Tycho’s precise data on the movements of the planet Mars led to Kepler’s discovery of his three laws of planetary motion.
Three years before the birth of Tycho Brahe, Copernicus had published “De revolutionibus orbium celestium,” in which he demonstrated that the Earth and the other planets revolved around the Sun, in contrast to the prevailing view that the Sun and the planets revolved around the Earth. Tycho took an intermediate position. He believed that all the known planets (except the Earth) revolved around the Sun. However, he thought that the Sun revolved around an immobile Earth, carrying the planets with it.
Tycho rightly believed that if the Earth moved, the observed position of the stars would appear to shift as the Earth changed position. Since he observed no change in the position of the stars during different seasons of the year, he concluded that the earth did not move. Tycho had the best astronomical equipment available at the time, but his instruments were not good enough to detect the tiny shift in position that the stars appear to make as the Earth revolves around the Sun.
References
University of Virginia: Tycho Brahe
http://galileo.phys.virginia.edu/classes/109N/1995/lectures/tychob.html
University of Tennessee – Knoxville: The Observations of Tycho Brahe
http://csep10.phys.utk.edu/astr161/lect/history/brahe.html
Wikipedia: Tycho Brahe
http://en.wikipedia.org/wiki/Tycho_Brahe
University of Cambridge: Tycho Brahe
http://www.hps.cam.ac.uk/starry/tycho.html
“The New Solar System” by Patricia Daniels
New Age Encyclopedia