  Sagittarius A* (Sgr A*) is a strong, compact radio source believed to be
powered by a super-massive black hole at the galactic center. Extinction by
dust and gas in the galactic plane prevents observing it optically, but its
position and proper motion have previously been estimated using radio
interferometry. We present new VLBI absolute astrometry measurements of its
precise position and proper motion in the frame of the third realization of the
International Celestial Reference Frame, ICRF3. The observations used were made
at 52 epochs on the VLBA at K-band (24 GHz) between June 2006 and August 2022.
We find the proper motion of Sgr A* to be -3.128 $\pm$ 0.042 mas/yr in right
ascension and -5.584 $\pm$ 0.075 mas/yr in declination, or 6.400 $\pm$ 0.073
mas/yr at a position angle of 209.26 $\pm$ 0.51 degrees. We also find its J2000
ICRF3 coordinates at the 2015.0 proper motion epoch to be
17$^h$45$^m$40.034047$^s$ $\pm$ 0.000018$^s$, -29$^o$00'28.21601'' $\pm$
0.00044''. In galactic coordinates, Sgr A* shows proper motion of -6.396 $\pm$
0.071 mas/yr in galactic longitude and -0.239 $\pm$ 0.045 mas/yr in galactic
latitude, indicating solar motion of 248.0 $\pm$ 2.8 km/sec in the galactic
plane and 9.3 $\pm$ 1.9 km/sec towards the north galactic pole.
