Tycho Brahe (1546 – 1601)

Tycho was born into a noble Danish family and was educated to be a lawyer and diplomat. He had a rather rowdy youth, and at one point his nose was cut off during a duel over a women. Throughout the rest of his life he wore an assortment of artificial noses, one of gold.

Although his family expected him to have a standard career in the government, he became interested in astronomy at an early age. The event that permanently oriented him toward an astronomical career was the appearance in 1572 of a “new star” or nova in the constellation of Cassiopeia.

The philosophy of the day, directly descended from Aristotle, held that the heavens were perfect and unchanging. Any apparent changes had to be local phenomena occurring in the atmosphere. This was the explanation commonly used for comets. Many months of observation on the “new star”, however, convinced Tycho that it had to be a celestial phenomenon, largely because no parallax could be detected. That is, it appeared to remain located in exactly the same spot on the celestial sphere when observed from any location on earth.

The well - connected Tycho was able to acquire an island in off the Danish coast and build an observatory to chart the heavens with unprecedented accuracy. Although he designed and built many precision astronomical instruments, none incorporated the telescope or other optics – all observations were ultimately made with the unaided eye. Thus, Tycho is often designated the “last great naked eye astronomer”. His star maps and the data on planetary positions were of such accuracy that Johannes Kepler was able to deduce that planetary orbits must be elliptical, rather than perfect circles, as had been assumed by both Ptolemy and Copernicus.