Device and Materials Modeling in PEM Fuel Cells (Astronomy and Astrophysics Library)

The book is an introduction to practical astrometry, dealing with the determination of positions, motions, distances and dimensions of celestial bodies ranging from quasars to artificial satellites. The main part is devoted to the description of instruments and observing techniques and also sketches the actual treatment of observations of physical quantities. Furthermore it deals with the basic properties of optical instruments and a detailed description of the atmospheric effects on observations. A brief summary of the main phenomena in positional astronomy and of data treatment is given. Although classical astrometric methods (photography, meridian circles, astrolabes) are described, emphasis is put on new, more precise techniques such as CCD, optical and radio interferometry, space astrometry, etc.