Discovery of the first methanol (CH3OH) maser in the Andromeda galaxy (M31)

Lorant O. Sjouwerman, Claire E. Murray, Ylva M. Pihlstrom, Vincent L. Fish, Esteban D. Araya

Published 2010-10-22Version 1

We present the first detection of a 6.7 GHz Class II methanol (CH3OH) maser in the Andromeda galaxy (M31). The CH3OH maser was found in a Very Large Array (VLA) survey during the fall of 2009. We have confirmed the methanol maser with the new Expanded VLA (EVLA), in operation since March 2010, but were unsuccessful in detecting a water maser at this location. A direct application for this methanol maser is the determination of the proper motion of M31, such as was obtained with water masers in M33 and IC10 previously. Unraveling the three-dimensional velocity of M31 would solve for the biggest unknown in the modeling of the dynamics and evolution of the Local Group of galaxies.