Distance of W3(OH) by VLBI annual parallax measurement
نویسندگان
چکیده
The most powerful tool for measuring distances within our Galaxy is the annual parallax. We carried out phase-referencing VLBI observations of H2O masers in the star forming region W3(OH) with respect to the extragalactic continuum source ICRF 0244+624 to measure their absolute proper motions. The measured annual parallax is 0.484 ± 0.004 milli-arcseconds which corresponds to a distance of 2.07 −0.02 kpc from the sun. This distance is consistent with photometric and kinematic distances from previous observations.
منابع مشابه
Water maser motions in W3(OH) and a determination of its distance
We report phase-referenced VLBA observations of H2O masers near the star-forming region W3(OH) to measure their parallax and absolute proper motions. The measured annual parallax is 0.489 ± 0.017 milli-arcseconds (2.04 ± 0.07 kpc) where the error is dominated by a systematic atmospheric contribution. This distance is consistent with photometric distances from previous observations and with the ...
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