Tycho Brahe and Enlightenment

What is the shape of the universe? Brahe’s model of the universe can be explained best with this model below. (p.409, Dictionary of Scientific Biography) In this model, Brahe describes the universe with the earth at the center. The sun orbits the earth while the other planets revolve around the sun in the order of Mercury, Venus, Mars, Jupiter, and Saturn. There is also a realm of fixed stars beyond the paths of the …

…permanent causes of error, such as atmospheric refraction. (Unfortunately, he thought refraction was negligible at altitudes above 70 ?.) This method of scientific reasoning was incredibly successful for Brahe. His estimate of the length of the tropical year was only 2” too small. He determined the precision of the equinoxes exactly at 51” (Sarton 65). He discovered the length of the year within one second (Abell, Morriso, and Wolff 34). Considering the quality of his instruments, such precision is almost uncanny.