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However, the positions of the mean objects in the DR1 release catalog were recalibrated using Gaia DR1 positions as additional constrains in the astrometric solution.  The Gaia measurements were given very high weight, as detailed in Magnier et al. (2016).  A comparison of Gaia and PanSTARRS positions for the objects in common yields a typical residual of 5 mas (1-sigma, 2-d), with a slightly higher component in the direction of right ascension.  This comparison may not fully reflect PanSTARRS position errors, because of the correlation in the quantities that weer were compared (Gaia measurements are included in the determination of individual PanSTARRS positions).

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Note that the stack object astrometry has not been recalibrated with Gaia constraints, and therefore is likely to include it still includes the larger systematic uncertainty from the 2MASS calibration.

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