Gaia is an ESA satellite project launched at Dec. 2013. It will map our
Galaxy in 3D by measuring six astrometric parameters (i.e. two
positions, two proper motions, parallax, and radial velocity) of one
billion stars over the whole sky. Astrometric accuracy of Gaia for G
type star is 5-16 μas for bright stars, 24 μas at V = 15 mag and 540 μas
at V = 20 mag, which is the highest accuracy that has ever been
achieved. Gaia simultaneously obtains low-resolution spectrum of each
star using Blue and Red Photometer (BP and RP: 330-680nm and 640-1000nm,
respectively). By the nature of Gaia, it will produce enormous amount of
complex data. Analyzing Gaia data is thus a challenging and huge task
requiring big-data experts and dedicated computing powers as well. In
this talk, I will give an overview of the Gaia mission and efforts for
Gaia data analysis in DPAC (Data Processing and Analysis Consortium).