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Sharpless 269 (S269) is one of a few HII regions in the outer spiral arm ofthe Milky Way with strong water maser emission. Based on data from the VeryLong Baseline Interferometry (VLBI) Exploration of Radio Astrometry (VERA)array, two parallax measurements have been published, which differ by nearly$2\sigma$. Each distance estimate supports a different structure for the outerarm. Moreover, given its large Galactocentric radii, S269 has special relevanceas its proper motion and parallax have been used to constrain the Galacticrotation curve at large radii. Using recent Very Long Baseline Array (VLBA)observations, we accurately measure the parallax and proper motion of the watermasers in S269. We interpret the position and motion of S269 in the context ofGalactic structure, and possible optical counterparts. S269's 22 GHz watermasers and two close-by quasars were observed at 16 epochs between 2015 and2016 using the VLBA. We measure an annual parallax for S269 of 0.241 $\pm$0.012 mas corresponding to a distance from the Sun of $4.15^{+0.22}_{-0.20}$kpc by fitting four maser spots. The mean proper motion for S269 was estimatedas $0.16\pm0.26$ mas $\rm{yr^{-1}}$ and $-0.51\pm0.26$ mas $\rm{yr^{-1}}$ for$\mu_{\alpha} \ cos \delta$ and $\mu_{\delta}$ respectively, which correspondsto the motion expected for a flat Galactic rotation curve at large radius. Thisdistance estimate, Galactic kinematic simulations and observations of othermassive young stars in the outer region support the existence of a kink in theouter arm at $l \approx$ 140 degrees. Additionally, we find more than 2,000optical sources in the Gaia DR2 catalog within 125 pc radius around the 3Dposition of the water maser emission; from those only three sources are likelymembers of the same stellar association that contains the young massive starresponsible for the maser emission (S269 IRS 2w).

Resolving the distance controversy for Sharpless 269: A possible kink in the outer arm