The International Year of Astronomy 2009 (IYA2009) celebrates not only Galileo Galilei’s innovative work in telescopic observational astronomy, but also the year that Johannes Kepler’s paradigm-setting work Astronomia Nova - which he wrote in Prague - was published. This, Kepler’s magnum opus contains the results of the astronomer’s ten year investigation of the motion of Mars and records the discovery of the first two of the three principles known as Kepler’s Laws of Planetary Motion. and Luděk Svoboda.