  The absolute position of Sgr A*, the compact radio source at the center of
the Milky Way, had been uncertain by several tens of milliarcseconds. Here we
report improved astrometric measurements of the absolute position and proper
motion of Sgr A*. Three epochs of phase-referencing observations were conducted
with the Very Long Baseline Array for Sgr A* at 22 and 43 GHz in 2019 and 2020.
Using extragalactic radio sources with submilliarcsecond-accurate positions as
reference, we determined the absolute position of Sgr A* at a reference epoch
2020.0 to be at $\alpha$(J2000) = $17^{\rm h} 45^{\rm m}40.^{\rm
s}032863~\pm~0.^{\rm s}000016$ and $\delta$(J2000) = $-29^{\circ} 00^{\prime}
28.^{''}24260~\pm~0.^{''}00047$, with an updated proper motion
$-3.152~\pm~0.011$ and $-5.586~\pm~0.006$ mas yr$^{-1}$ in the easterly and
northerly directions, respectively.

Astrophysics of Galaxies;Instrumentation and Methods for Astrophysics