SIMBAD references

Gaia is designed as a scanning satellite to collect data for high-precision astrometry with standard errors of 10 microarcseconds of positions, parallaxes and annual proper motions for stars brighter than V = 15 mag and sub-milliarcsecond precision for all stars brighter than V = 20 mag. Multicolor photometry will be obtained for these about one billion stars. An overview of the Gaia mission with respect to multicolor photometry of stars is given. The detection of supernovae and solar system objects, and the possibility for surface photometry are discussed. An appendix on Gaia mapping and photometry contains the three sections: samples and patches, precision of aperture photometry, mapping and photometry.