Gaia is the next generation astrometric mission from ESA, due to be launched in late 2011. It will survey the entire sky down to a magnitude of approximately V=20, detecting about one billion stars, or about 1% of the Galactic stellar population. Together with the stellar sample, several million galaxies, perhaps half a million quasars and thousands of solar system objects will also be detected. In addition to astrometric information, radial velocities will be measured for the brightest objects, and astrophysical parameters will be determined from low resolution spectra.
 


The DPAC (Data processing and analysis consortium) is responsible for the data handling from the mission. DPAC is divided into eight subgroups, called coordinating units, each of which is responsible for a different aspect of the Gaia data processing.


The MPIA hosts one of two Gaia teams in Heidelberg (the other is at ARI), funded primarily by the German space agency, the DLR. This team of four full-time postdocs, Vivi Tsalmantza, Kester Smith, Chao Liu, and Rene Andrae, led by Coryn Bailer-Jones, contribute to CU8 "Astrophysical Parameters" by developing algorithms to classify and interpret the Gaia data. (Coryn is also the overall manager of CU8.) We are building the Gaia classification machine - the "Discrete Source Classifier" - a probabilistic classifier to identify all Gaia sources. We also provide the algorithm for extracting physical parameters for single and binary stars from the BP/RP spectra and astrometry. The group additionally maintains the CU8 datamodel and contributes to the galaxy parametrizer. In parallel to Gaia we are involved in related projects involving the application of pattern recognition methods to large data sets.