THE BIRTH OF ASTROPHYSICS
Galileo's telescope prompted renewed enthusiasm for observational astronomy in the early seventeenth century, the development of the spectrometer two centuries later spawned a vigorous new science that focused on the dynamics, chemical properties, and evolution of celestial bodies.
The study of astrophysics, as it was called, began modestly in Munich in 1814, when physicist and telescope-maker Joseph von Fraunhofer passed the light of the Sun and stars through a spectrometer— essentially a prism that broke the light down into the colors of the spectrum. He noticed that the spectra had hundreds of dark lines, like fence slats, running across them. Although Fraunhofer realized that the lines were important, their meaning eluded him and other scientists for 45 years.