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We have used the VLBA to measure the annual parallax of the H2O masers in thestar-forming region IRAS 00420+5530. This measurement yields a direct distanceestimate of 2.17 +/- 0.05 kpc (<3%), which disagrees substantially with thestandard kinematic distance estimate of ~4.6 kpc (according to the rotationcurve of Brand and Blitz 1993), as well as most of the broad range of distances(1.7-7.7 kpc) used in various astrophysical analyses in the literature. The3-dimensional space velocity of IRAS 00420+5530 at this new, more accuratedistance implies a substantial non-circular and anomalously slow Galacticorbit, consistent with similar observations of W3(OH) (Xu et al., 2006;Hachisuka et al. 2006), as well as line-of-sight velocity residuals in therotation curve analysis of Brand and Blitz (1993). The Perseus spiral arm ofthe Galaxy is thus more than a factor of two closer than previously presumed,and exhibits motions substantially at odds with axisymmetric models of therotating Galaxy.

A Precise Distance to IRAS 00420+5530 via H2O Maser Parallax with the VLBA