Die Bewegungen der Sterne und ihre Bedeutung in der galaktischen Astronomie (Karl-Schwarzschild-Vorlesung 1982)

Attention is given to the study of the statistical characteristics of the proper motion of stars conducted by Kobold (1885) on the basis of the method proposed by Bessel. The Schwarzschild model, and the significance of the study of stellar velocities in fundamental astronomy and astrophysics are also discussed. The kinematic properties of the stars in the vicinity of the sun are considered along with the dynamic determination of the local standard of rest, relations between the stellar orbits and the evolution of the Galaxy, and a number of problems concerning the observational data. It is pointed out that the number and quality of the available data are a decisive factor in the discussed investigations. Topics examined are related to the chemical composition of the stars, the density of the interstellar gas and its physical properties, a study of the spiral structure of the Galaxy, and information provided by the various components of the velocity of a star.