204 A SHORT HISTORY OF SCIENCE 



and attention he was expected to give to subjects more highly 

 esteemed for a man of birth and fortune. 



From a lunar eclipse which took place while he was at Leipsic, 

 Tycho foretold wet weather, which also turned out to be correct. 



Here, too, he began his life work of procuring and improving the 

 best instruments for astronomical observations, at the same time 

 testing and correcting their errors. Returning to Denmark from 

 travels in Germany, his predilection for astronomy was powerfully 

 stimulated by the appearance in the constellation Cassiopeia, in 

 November, 1572, of a brilliant new star, which remained visible for 

 16 months. The great importance attached to this occurrence by 

 Tycho and his contemporaries was due to the evidence it afforded 

 against the truth of the Aristotelian conviction that the heavens 

 were immutable, since Tycho's careful observations showed that 

 the star must certainly be more distant than the moon, and that it 

 had no share in the planetary motions. He reluctantly published 

 an account of the new star, expressing still his adherence to 

 the current pre-Copernican notions of crystalline spheres for the 

 different heavenly bodies and of atmospheric comets, all com- 

 bined with astrological reflections and inferences, as illustrated by 

 the following passages from Dreyer's biography : 



The star was at first like Venus and Jupiter, and its effects will 

 therefore first be pleasant ; but as it then became like Mars, there will 

 next come a period of wars, seditions, captivity, and death of princes 

 and destruction of cities, together with dryness and fiery meteors in 

 the air, pestilence, and venomous snakes. Lastly, the star became 

 like Saturn, and there will therefore, finally, come a time of want, 

 death, imprisonment, and all kinds of sad things. 



As the star seen by the wise men foretold the birth of Christ, 

 the new one was generally supposed to announce His last coming 

 and the end of the world. 



That an unusual celestial phenomenon occurring at that particular 

 moment should have been considered as indicating troublous times, 

 is extremely natural when we consider the state of Europe in 1573. 

 The tremendous rebellion against the Papal supremacy, which for a 

 long time had seemed destined to end in the complete overthrow of 



