Status Report

Mapping Spiral Structure on the far side of the Milky Way

By SpaceRef Editor
October 24, 2017
Filed under , ,

Alberto Sanna, Mark J. Reid, Thomas M. Dame, Karl M. Menten, Andreas Brunthaler
(Submitted on 17 Oct 2017)

Little is known about the portion of the Milky Way lying beyond the Galactic center at distances of more than 9 kilo-parsec from the Sun. These regions are opaque at optical wavelengths due to absorption by interstellar dust, and distances are very large and hard to measure. We report a direct trigonometric parallax distance of 20.4_{-2.2}^{+2.8} kilo-parsec obtained with the Very Long Baseline Array to a water maser source in a region of active star formation. These measurements allow us to shed light on Galactic spiral structure by locating the Scutum-Centaurus spiral arm as it passes through the far side of the Milky Way, and to validate a kinematic method for determining distances in this region based on transverse motions.

Comments:    21 pages, 5 figures, 4 tables, published in Science, October 13 issue
Subjects:    Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
Journal reference:    Science 13 Oct 2017: Vol. 358, Issue 6360, pp. 227-230
DOI:    10.1126/science.aan5452
Cite as:    arXiv:1710.06489 [astro-ph.GA] (or arXiv:1710.06489v1 [astro-ph.GA] for this version)
Submission history
From: Alberto Sanna
[v1] Tue, 17 Oct 2017 20:08:07 GMT (246kb,D)

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