Related papers: Betelgeuse, the Prototypical Red Supergiant
The bright supergiant, Betelgeuse (Alpha Orionis, HD 39801) experienced a visual dimming during 2019 December and the first quarter of 2020 reaching an historic minimum 2020 February 7$-$13. During 2019 September-November, prior to the…
The 'Great Dimming' of the prototypical red supergiant Betelgeuse, which occurred between December 2019 and April 2020, gives us unprecedented insight into the processes occurring on the stellar surface and in the inner wind of this type of…
The semi-regular variable star Betelgeuse is undergoing an historical minimum of its brightness. An 8 year series of visual and V-band CCD observations started at the end of 2011 is presented and discussed. Visual methods for comparing…
Betelgeuse is a well known bright red supergiant that shows semi-regular variations with four approximate periods of 2200, 420, 230, and 185 days. While the longest period was customarily regarded as LSP (long secondary period) of unknown…
Since October 2019, Betelgeuse began to dim noticeably and by January 2020 its brightness had dropped by a factor of approximately 2.5, demoting it from the position of the top (apparent) brightest 11 th star to the 21 st!!! Astronomers…
The dynamics of the surface and inner atmosphere of the red supergiant star Betelgeuse are the subject of numerous high angular resolution and spectroscopic studies. Here, we present three-telescope interferometric data obtained at 11.15…
The recent pre-print by Saio et al. 2023 argues that the supergiant Betelgeuse is already undergoing carbon burning, based on the assumption that all of its light variations are caused by radial pulsations. However, the angular diameter…
Recent numerical simulations by Freytag et al. of the outer convection envelope of the cool super-giant Betelgeuse, have shown that the fluctuations in the star's apparent luminosity may be caused by giant cell convection. These simulations…
We investigate the merger between a 16 solar mass star, on its way to becoming a red supergiant (RSG), and a 4 solar mass main-sequence companion. Our study employs three-dimensional hydrodynamic simulations using the state-of-the-art…
The dramatic dimming episode of the red supergiant Betelgeuse in 2019/2020, caused by a partial darkening of the stellar disk, has highlighted gaps in the understanding of the evolution of massive stars. We analyzed numerical models to…
The processes that shape the extended atmospheres of red supergiants (RSGs), heat their chromospheres, create molecular reservoirs, drive mass loss, and create dust remain poorly understood. Betelgeuse's V-band "Great Dimming" event of 2019…
Betelgeuse is an example of a cool super-giant displaying brightness fluctuations and irregular surface structures. Simulations by Freytag et al. (2002) of the convective envelope of the star have shown that the fluctuations in the star's…
Critical transitions occur in complex dynamical systems, when the system dynamics undergoes a regime shift. These can often occur with little change in the mean amplitude of system response prior to the actual time of transition. The recent…
In 2019 October Betelgeuse began a decline in V-band brightness that went beyond the minimum expected from its quasi-periodic ~420 day cycle, becoming the faintest in recorded photometric history. Observations obtained in 2019 December with…
Betelgeuse is an M supergiant with a complex and extended atmosphere, which also harbors spots and giant granules at its surface. A possible magnetic field could contribute to the mass loss and to the heating of the outer atmosphere. We…
Context. The mass-loss mechanism of cool massive evolved stars is poorly understood. The proximity of Betelgeuse makes it an appealing target to study its atmosphere, map the shape of its envelope, and follow the structure of its wind from…
Betelgeuse has gone through a sudden shift in its brightness and dimmed mysteriously. This is likely caused by a hot blob of plasma ejected from Betelgeuse and then cooled to obscuring dust. If true, it is a remarkable opportunity to…
The evolved stages of massive stars are poorly understood, but invaluable constraints can be derived from spatially resolved observations of nearby red supergiants, such as Betelgeuse. Atacama Large Millimeter/submillimeter Array (ALMA)…
The physical mechanism through which the outgoing material of massive red supergiants is accelerated above the escape velocity is unclear. Thanks to the transparency of its circumstellar envelope, the nearby red supergiant Betelgeuse gives…
We assess whether gravity darkening, induced by a tidal interaction during a stellar fly-by, might be sufficient to explain the Great Dimming of Betelgeuse. Adopting several simple approximations, we calculate the tidal deformation and…