Composed of a set of lectures and tutorial reviews, this book stems from a summer school devoted to the gravitational aspects of the sun and their geophysical consequences. Contribitions elaborate on the gravitational distortions of the sun which can be used to gain some knowledge of the sun's interior and surface phenomena but which also influences the sun's irradience and thus ultimately the earth's climate. Last but not least, it is shown that these small distortions constitute a formidable challenge to solar astrometry, and the final part of the book describes the observational difficulties in defining unequivocally the solar diameter.

Inhalt

A Guide to the Book.- A Guide to the Book.- The Figure of the Sun, Astrophysical Consequences. A Tutorial.- The Figure of the Sun, Astrophysical Consequences. A Tutorial.- Solar Oscillations.- Helioseismology: A Fantastic Tool to Probe the Interior of the Sun.- Detection of Solar Eigenmodes.- Variations in the Solar Irradiance.- Solar Ultraviolet Irradiance: Origins, Measurements, and Models.- Total Solar and Spectral Irradiance Variations from Near-UV to Infrared.- Mesurement of the Solar Diameter.- Atmospheric Turbulence and Solar Diameter Measurement.- Solar Astrometry with the Astrolabe of Santiago.- Measurements of the Sun's Radius at Calern Observatory.