Louisiana State University | 2020 Jan 06
LSU astronomy researchers estimate the peak of brightness and explosion of luminous star brighter than any other in the Milky Way galaxy.
Currently, the faint star V Sagittae, V Sge, in the constellation Sagitta, is barely visible, even in mid-sized telescopes. However, around the year 2083, this innocent star will explode, becoming as bright as Sirius, the brightest star visible in the night sky. During this time of eruption, V Sge will be the most luminous star in the Milky Way galaxy. This prediction is being presented for the first time at the 235th American Astronomical Society meeting in Honolulu, HI, by astronomers Bradley E. Schaefer, Juhan Frank, and Manos Chatzopoulos, with the Louisiana State University Department of Physics & Astronomy.
“We now have a strong prediction for the future of V Sge,” said Professor Emeritus Bradley E. Schaefer, LSU Department of Physics & Astronomy. “Over the next few decades, the star will brighten rapidly. Around the year 2083, its accretion rate will rise catastrophically, spilling mass at incredibly high rates onto the white dwarf, with this material blazing away. In the final days of this death-spiral, all of the mass from the companion star will fall onto the white dwarf, creating a super-massive wind from the merging star, appearing as bright as Sirius, possibly even as bright as Venus.”
V Sge is a star system in a large and diverse class called Cataclysmic Variables, CVs, consisting of an ordinary star in a binary orbit around a white dwarf star, where the normal star's mass is slowly falling onto the white dwarf. CVs include multiple types of binary stars, often with spectacular behavior. V Sge is the most extreme of all the CVs, approximately 100 times more luminous than all other known CVs, and is powering a massive stellar wind, equal to the winds of the most massive stars prior to their deaths. These two extreme properties are caused by the fact that the normal star is 3.9 times more massive than the white dwarf. ...