This volume collects the invited contributions and plenary sessions presented at the Eighth Scientific Meeting of the Spanish Astronomical Society (Sociedad Española de Astronomía, SEA) held on July 7-11, 2008 in Santander. These contributions cover all fields of astronomy and astrophysics, i.e., the Sun and solar system, the galaxy and its components, galaxies and cosmology, observatories and instrumentation, as well as astronomy teaching and dissemination. Further plenary sessions were devoted to selected hot topics, including the exploration of the solar system, gravitational lensing, exoplanets, X-ray binaries, solar magnetism, gravitational waves, the ALHAMBRA collaboration, and the OSIRIS instrument on the new 10-m GTC. Abstracts of the contributions presented at the parallels sessions and posters are also included in the book. Complete versions of those papers are available online.