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We combined data from the Two‐Micron All Sky Survey (2MASS) and USNO‐A2.0 catalogues in order to derive the absolute proper motions of about 280 million stars distributed all over the sky excluding a small region near the Galactic Centre, in the magnitude range 12 < B < 19 mag. The proper motions were derived from the 2MASS Point Sources and USNO‐A2.0 catalogue positions with a mean epoch difference of about 45 years for the Northern hemisphere and about 17 years for the Southern one. The zero‐point of the absolute proper motion frame (the ‘absolute calibration’) was specified with the use of about 1.45 million galaxies from 2MASS. Most of the systematic zonal errors inherent in the USNO‐A2.0 catalogue were eliminated before the calculation of proper motions. The mean formal error of absolute calibration is less than 1 mas yr−1. The XPM Catalogue will be available via CDS in Strasbourg during 2010. The generated catalogue contains the International Celestial Reference System positions of stars for the J2000 epoch, original absolute proper motions, as well as B, R, J, H and K magnitudes. A comparison of the proper motions obtained in this work with the data of other recent catalogues of quasars was fulfilled.

We present a catalogue that contains about 420 million absolute proper motions of stars. It was derived from the combination of positions from Gaia DR1 and 2MASS, with a mean difference of epochs of about 15 yr. Most of the systematic zonal errors inherent in the 2MASS Catalogue were eliminated before deriving the absolute proper motions. The absolute calibration procedure (zero-pointing of the proper motions) was carried out using about 1.6 million positions of extragalactic sources. The mean formal error of the absolute calibration is less than 0.35 mas yr−1. The derived proper motions cover the whole celestial sphere without gaps for a range of stellar magnitudes from 8 to 21 mag. In the sky areas where the extragalactic sources are invisible (the avoidance zone), a dedicated procedure was used that transforms the relative proper motions into absolute ones. The rms error of proper motions depends on stellar magnitude and ranges from 2–5 mas yr−1 for stars with 10 mag &lt; G &lt; 17 mag to 5–10 mas yr−1 for faint ones. The present catalogue contains the Gaia DR1 positions of stars for the J2015 epoch. The system of the PMA proper motions does not depend on the systematic errors of the 2MASS positions, and in the range from 14 to 21 mag represents an independent realization of a quasi-inertial reference frame in the optical and near-infrared wavelength range. The Catalogue also contains stellar magnitudes taken from the Gaia DR1 and 2MASS catalogues. A comparison of the PMA proper motions of stars with similar data from certain recent catalogues has been undertaken.

XPM-1.0 is the regular version of the XPM catalogue. In comparison with XPM, this astrometric catalogue of about 280 millions stars covering the entire sky from −90 • to +90 • in declination and in the magnitude range 10 < B < 22 mag is somewhat improved. The general procedural steps were followed as for XPM, but some of these were performed on a more sophisticated level. The XPM-1.0 catalogue contains the star positions, the proper motions and the Two-Micron All-Sky Survey (2MASS) and United States Naval Observatory (USNO) photometry of about 280 million sources. We present some investigations of the absolute proper motions of the XPM-1.0 catalogue and also important information for users of the catalogue. Unlike the previous version, XPM-1.0 contains proper motions over the whole sky without gaps. In fields covering the zone of avoidance or those that contain fewer than 25 galaxies, quasi-absolute calibration was performed. The proper motion errors vary from 3 to 10 mas yr −1 , depending on a specific field. The zero-point of the absolute proper motion frame (the absolute calibration) was specified with more than one million galaxies from 2MASS and USNO-A2.0. The mean formal error of absolute calibration is less than 1 mas yr −1 .