Tycho's SupernovaIn 1572, Danish astronomer Tycho Brahe began his meticulous observations of the supernova discovered in the W-shaped constellation of Cassiopeia. (Brahe was at the beginning of his career in 1572, and it was this supernova that inspired him to devote his lifetime to making accurate measurements of the positions of the stars and planets.) For two weeks it was brighter than any other star in the sky and visible in daytime. By month's end, it began to fade but it remained visible to the naked eye for about 16 months until Mar 1574. Thus 16th-century astronomers learned that the heavens were not immutable, as had been believed. Brahe's book on his observations, De Nova Stella, originated the word “nova.”« |
