Enthusiastic reception for ESA's Gaia mission
1 December 1998
The Gaia workshop, held at the Lorentz Centre in Leiden (23-27 November), provided many European scientists with an opportunity to consider the scientific potential of the Gaia astrometric mission in the light of the technical study of the instrument just completed by Matra Marconi Space.The Gaia mission aims to observe more than one thousand million (1 billion) stars and for each of these stars to provide accurate three-dimensional positions, space velocities, and related information (for example, broad-band photometric measurements).
From the workshop discussions and presentations it is clear that only a large scale galactic survey reaching microarcsecond accuracy for the astrometric parameters can rigorously address the fundamental questions of the formation and evolution of our Galaxy. As a by-product of the mission, many important astrophysical issues will also be addressed. These include distance scale and luminosity calibrations, and the search for dark matter in the Galaxy. In addition Gaia will detect large numbers of extrasolar planets and brown dwarfs, hundreds of thousands of new asteroids and millions of multiple star systems. By the end of the five-year mission Gaia observations will result in an unprecedented stereoscopic census of the Galaxy.
In addition to lively discussions on the scientific potential of Gaia, the workshop also considered the potential difficulties associated with the large data volume which will be created by Gaia. A five-year mission which will generate astrometric and photometric measurements for one billion stars presents a challange in terms of data storage and data analysis. Fortunately many large-scale projects are already considering solutions to these problems - solutions from which Gaia can benefit.