Proper motion sky survey of 2.7 million stars with the Bordeaux automated CCD meridian circle

International audienceThe Bordeaux observatory astrometric group has performed significant efforts to produce and exploit large data base surveys. This effort has been realized to extend and densify the ICRS materialized by Tycho2 catalogue. This effort concerns the systematic re-observation of the Bordeaux Carte du Ciel zone with the Bordeaux automatic CCD meridian circle; it also concerns the digitization of ancient plate archives and the exploitation of large sky surveys such as the AC2000.2 catalogue, the USNO-A2.0 catalogue and the unpublished Yellow Sky (YS3) USNO catalogue.The whole effort led to the construction of three astrometric catalogues (M2000, PM2000 and CdC2000) of a position and proper motion (sigma~1-6 mas/yr) down to V~16.4 of 1/20 of the celestial sphere. The high precision achieved, allowed us to test the precision of the present day reference catalogues such as 2MASS and UCAC2 and to reveal systematic offsets in them. Due to its accurate proper motions, this catalogue constitutes a rich database for the kinematic analysis of Galactic stellar populations