The Brightening of the Red Supergiant alpha Ori
ATel #9503; R. P. Wasatonic and E. F. Guinan (Villanova University)
on 18 Sep 2016; 19:08 UT
Credential Certification: Edward Guinan (edward.guinan@villanova.edu)
Subjects: Optical, Request for Observations, Star, Variables
Referred to by ATel #: 16374
We have been carrying out V-band and Wing TiO-band and Near-IR photoelectric photometry of the semi-regular variable red supergiant alpha Ori (Betelgeuse) over last 20 yrs. Photometry obtained during early to mid September 2016 indicates that the star is at (or near) maximum light at = +0.29 mag. Measures of TiO-band and near-IR colors indicate that alpha Ori has undergone a temperature increase of about +120 K and has an estimated spectral type of M0.5 Iab. Because alpha Ori is one of the nearest Type II SN progenitors, it an important star to monitor. This would be an opportune time to secure spectroscopy, polarization, interferometry, and radio observations of the star while near maximum brightness.