Solar diameter, eclipses and transits: the importance of ground-based   observations
  The lifetime of a satellite is limited, and its calibration may be not stable, it is necessary to continue ground-based measures of the solar diameter with methods less affected by atmospheric turbulence, and optical aberrations: planetary transits and total eclipses. The state of art, advantages and limits of these methods are considered. 
Costantino Sigismondi
astro-ph.IM astro-ph.SR