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Description
We combined data from 2MASS and USNO-A2.0 catalogues in order to derive the absolute proper motions of about 314 million stars distributed all over the sky without gaps in the V magnitude range 10 mag to 20 mag. The proper motions were derived from 2MASS Point Sources and USNO-A2.0 catalogue positions, with the mean epoch difference of about 45 years for the northern hemisphere, and about 17 years for the southern one. Most of the systematic zonal errors inherent in the USNO-A2.0 catalogue were eliminated before calculation of the proper motions. The zero-point of the absolute proper motion frame (the absolute calibration) was specified with the use of about 1.1 million of extended sources from 2MASS and USNO-A2.0. In fields covering the zone of avoidance or those that contain fewer than 25 galaxies, quasi-absolute calibration was performed. The mean formal error of absolute calibration is less than 1 mas/yr. The catalogue contains ICRS positions of stars at 2000.0 epoch, original absolute proper motions, as well as F, J, V, N magnitudes from GSC2.3; B, R magnitudes from USNO-A2.0 and J, H, Ks magnitudes from 2MASS.
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