Speaker
Description
Antares is one of the nearest red supergiant and is similar to Betelgeuse in many aspects, yet it has received considerably less attention. We constructed the longest and most precise light curve of Antares to date using nine years of photometric observations from the Solar Mass Ejection Imager (SMEI) space instrument, which gave us an unprecedented view of the light variations of the star. We complemented these data with long-term radial velocity measurements from the STELLA telescope and from the literature.
The corrected light curve and radial velocity measurements reveal several periodic signals, including a long secondary period of about 2000 days and multiple radial pulsation modes. Based on the phase difference between the photometric and radial velocity variations, we suggest that the long secondary period may be caused by a low-mass, close companion, analogous to Betelgeuse. Finally, analysis of the radial pulsations and comparison with stellar models allow us to estimate the physical parameters and distance of Antares independently of previous methods.