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We report our measurement of the trigonometric distance and proper motion IRAS 20056+3350, obtained from the annual parallax of H2O masers. Our distance of D = 4.69 +0.65-0.51 kpc, which is more than two 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. Using our distance we re-evaluate past observations to reveal IRAS 20056+3350 as a site of massive star formation at a young stage of evolution. This result is consistent with the spectral energy distribution of the source evaluated with published photometric data from UKIDSS, WISE, AKARI, IRAS and sub-millimetre continuum. Both analytical approaches reveal the luminosity of the region to be 2.4 x 10^4 Lo, and suggest that IRAS 20056+3350 is forming an embedded star of 16 Mo. We estimated the proper motion of IRAS 20056+3350 to be ($mu_{alpha}cosdelta$, $mu_{delta}$) = ($-2.62pm0.33$, $-5.65pm0.52$) mas yr$^{-1}$ from the group motion of H$_{2}$O masers, and use our results to estimate the angular velocity of Galactic rotation at the Galactocentric distance of the Sun, $Omega_{0} = 28.71pm0.63$ km s$^{-1}$ kpc$^{-1}$, which is consistent with the values obtained for other tangent point and Solar circle objects.
We present results of Chandra ACIS-I and Karl G. Jansky Very Large Array (VLA) 6 cm continuum observations of the IRAS 20126+4104 massive star forming region. We detect 150 X-ray sources within the 17 arcmin x 17 arcmin ACIS-I field, and a total of 1
Context. With the latest infrared surveys, the number of massive protostellar candidates has increased significantly. New studies have posed additional questions on important issues about the formation, evolution, and other phenomena related to them.
A multi-wavelength investigation of the star forming complex IRAS 20286+4105, located in the Cygnus-X region, is presented here. Near-infrared K-band data is used to revisit the cluster / stellar group identified in previous studies. The radio contin
Direct observations of accretion disks around high-mass young stellar objects would help to discriminate between different models of formation of massive stars. However, given the complexity of massive star forming regions, such studies are still lim
We have analyzed the Atacama Large Millimeter/submillimeter Array (ALMA) cycle 2 data of band 6 toward the G345.4938+01.4677 massive young protostellar object (G345.5+1.47 MYSO) in the IRAS 16562--3959 high-mass star-forming region with an angular re