We report our measurements of the trigonometric distance and proper motion of IRAS 20056+3350, obtained from the annual parallax of H2O masers. Our distance of D = 4:69+0:65 -0:51 kpc, which is 2.8 times larger than the near kinematic distance adopted in the literature, places IRAS 20056+3350 at the leading tip of the Local arm and proximal to the Solar circle. We estimated the proper motion of IRAS 20056+3350 to be (μα cos δ, μδ) = (—2:62 ± 0:33, —5:65 ± 0:52) mas yr-1 from the group motion of H2O masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, Ω0 = 29:75 ± 2:29 km s-1 kpc-1, which is consistent with the values obtained for other tangent points and Solar circle objects.

ABSTRACT
1. INTRODUCTION
2. Observations
3. RESULTS
4. DISCUSSION
    4.1. Proper Motion of IRAS 20056+3350
    4.2. Galactic Structure: Local Arm
    4.3. Evaluation of the 0 Galactic Constant
REFERENCES

• Ross A. Burns(Graduate School of Science and Engineering, Kagoshima University)
• Takumi Nagayama(Mizusawa VLBI Observatory, National Astronomical Observatory of Japan)
• Toshihiro Handa(Graduate School of Science and Engineering, Kagoshima University)
• Toshihiro Omodaka(Graduate School of Science and Engineering, Kagoshima University)
• Akiharu Nakagawa(Graduate School of Science and Engineering, Kagoshima University)
• Hiroyuki Nakanishi(Graduate School of Science and Engineering, Kagoshima University)
• Masahiko Hayashi(National Astronomical Observatory of Japan/School of Mathematical and Physical Science, The Graduate University for Advanced Studies)
• Makoto Shizugami(Mizusawa VLBI Observatory, National Astronomical Observatory of Japan)