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arXiv · 2603.05896

An updated model for the Perseus Spiral Arm from Trigonometric Parallax and 3-dimensional kinematic distances of distant massive stars

Lucas J. Hyland·Mark J. Reid·Simon P. Ellingsen·Andreas Brunthaler·Xing-Wu Zheng·Karl M. Menten
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Abstract

We report trigonometric parallaxes and proper motions for three water masers and one methanol maser obtained with the VLBA as part of the BeSSeL Survey. Incorporating these parallaxes with 3-dimensional kinematic distances, we refine the position and pitch angle of the Perseus spiral arm in the 1$^\mathrm{st}$ Galactic quadrant. Extrapolating the Perseus and Sagittarius arm locations to beyond the Galactic Center, we find that they intersect at an approximate Galactocentric azimuth of ${200^\circ}$ and radius of $5.6$~kpc.

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Lucas J. Hyland, Mark J. Reid, Simon P. Ellingsen, Andreas Brunthaler, Xing-Wu Zheng, Karl M. Menten. 2026-03-06. An updated model for the Perseus Spiral Arm from Trigonometric Parallax and 3-dimensional kinematic distances of distant massive stars. https://arxiv.org/abs/2603.05896

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