Life, the universe and everything, with GAIA
Abstract:Great things are expected of the GAIA Observatory, currently expected to launch in 2011. Gerry Gilmore explains how it will provide accurate measurements that will help us understand the formation of the Milky Way and the distribution of dark matter.
The GAIA Observatory, ESA’s Cornerstone 6 mission, addresses the origin and evolution of our galaxy, and a host of other scientific challenges. GAIA will provide unprecedented positional and radial velocity measurements with the accuracies needed to produce a stereoscopic and kinematic census of about one billion stars in our galaxy and throughout the Local Group, about 1% of the galactic stellar population. Combined with astrophysical information for each star, provided by on-board multicolour photometry, these data will have the precision and depth necessary to address the three key questions which underlie the GAIA science case: l when did the stars in the Milky Way form? l when and how was the Milky Way assembled? l what is the distribution of dark matter in our galaxy? The accurate stellar data acquired for this purpose will also have an enormous impact on all areas of stellar astrophysics, including luminosity calibrations, structural studies, and the cosmic distance scale. Additional scientific products include detection and orbital classification of tens of thousands of extrasolar planetary systems, a comprehensive survey of objects ranging from huge numbers of minor bodies in our solar system, including near-Earth objects, through galaxies in the nearby universe, to some 500 000 distant quasars. GAIA will also provide several stringent new tests of general relativity and cosmology.
Document Type: Research Article
Publication date: October 1, 2001