American Astronomical Society, Astrophysical Journal Letters, 2(799), p. L16, 2015
DOI: 10.1088/2041-8205/799/2/l16
Full text: Download
We present the first spectrum of the most luminous infrared star in M33, and use it to demonstrate that the object is almost certainly a binary composed of a massive O star and a dust-enshrouded red hypergiant. This is the most luminous symbiotic binary ever discovered. Its radial velocity is an excellent match to that of the hydrogen gas in the disk of M33, supporting our interpretation that it is a very young and massive binary star. © 2015. The American Astronomical Society. All rights reserved.