Used with
permission of Maiken Naylor, University at Buffalo, Buffalo, NY, USA,
http://ublib.buffalo.edu/libraries/units/sel/exhibits/stamps
Tycho Brahe (1546-1601) was the last and greatest of the naked-eye astronomers, rivalled only perhaps by Hipparchus. His book on his observations of an exploding star, De Nova Stella, gives us the word "nova." His many painstaking observations were passed on to his assistant Kepler, who used them to derive his three laws of planetary motion in a heliocentric universe, while Tycho himself had remained an adherent of the Ptolemaic geocentric world view.