# The Mass of the Milky Way and M31 Using the Method of Least Action

@article{Phelps2013TheMO,
title={The Mass of the Milky Way and M31 Using the Method of Least Action},
author={Steven Phelps and Adi Nusser and Vincent Desjacques},
journal={The Astrophysical Journal},
year={2013},
volume={775},
pages={102}
}
• Published 17 June 2013
• Physics
• The Astrophysical Journal
We constrain the most likely range of masses for the Milky Way (MW) and M31 using an application of the numerical action method (NAM) that optimizes the fit to observed parameters over a large ensemble of NAM-generated solutions. Our 95% confidence level mass ranges, 1.5-4.5 × 1012 M ☉ for MW and 1.5-5.5 × 1012 M ☉ for M31, are consistent with the upper range of estimates from other methods and suggests that a larger proportion of the total mass becomes detectable when the peculiar motions of… Expand

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