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The IC133 Water Vapor Maser in the Galaxy M33: A Geometric Distance

A. L. Argon·L. J. Greenhill·J. M. Moran·M. J. Reid·K. M. Menten·M. Inoue
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Abstract

We report on the results of a 14 year long VLBI study of proper motions in the IC133 H2O maser source in the galaxy M33. The method of Ordered Motion Parallax was used to model the 3-dimensional structure and dynamics of IC133 and obtain a distance estimate, 800 +/- 180 kpc. Our technique for determining the distance to M33 is independent of calibrations common to other distance indicators, such as Cepheid Period-Luminosity relations, and therefore provides an important check for previous distance determinations.

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A. L. Argon, L. J. Greenhill, J. M. Moran, M. J. Reid, K. M. Menten, M. Inoue. 2004-07-22. The IC133 Water Vapor Maser in the Galaxy M33: A Geometric Distance. https://doi.org/10.1086/424731

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