The German mathematician and physicist Gustav Kirchhoff died in Berlin. Together with Robert Bunsen and Joseph von Fraunhofer, he laid the foundations for the spectroscope, discovering that spectral rays, which Fraunhofer had observed years earlier, were connected to the chemical composition and to the atomic status of the elements that emitted or absorbed light. Thanks to the spectroscope, astronomy and astrophysics it has been possible to reconstruct in less than a century the physics and chemical composition of the celestial bodies and of a good part of the universe surrounding them. Due to an accident that happened when he was young, Kirchhoff was constricted to a wheelchair but neither his good humor nor his scientific activity were hampered by the disability.