By Deepa Jain published September 11, 2024
A new theoretical study proposes that Betelgeuse has a sunlike companion that orbits it and may be responsible for its perplexing periodic brightening.
If you train a telescope on Betelgeuse for weeks, you'll see it dimming, then brightening, then dimming again. These pulsations stretch over roughly 400 days, although the 2020 "Great Dimming" event reveals such periodicity may occasionally go awry. But if you plotted Betelgeuse's light intensity over years, you'd find these 400-day-long heartbeats superimposed on a much larger, slower heartbeat. Technically called a long secondary period (LSP), this second type of heartbeat lasts about six years, or 2,170 days, in Betelgeuse's case.
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Ultimately, only one scenario could explain all of Betelgeuse's parameters: a companion star that plows through dust clouds enveloping Betelgeuse.
According to the team's hypothesis, when the companion star — which the team calls "Betelbuddy" — sails into view of Earth, it temporarily disperses the clouds of dust surrounding its partner. Because this dust typically blocks Betelgeuse, its absence causes the star to look brighter from Earth's point of view.
https://www.livescience.com/space/astronomy/betelgeuse-may-have-a-sunlike-companion-study-suggestsI have no idea if the video in the OP goes into this - it looks too sensational and loaded with ads to be worth watching.
Their paper (not yet peer-reviewed):
A Buddy for Betelgeuse: Binarity as the Origin of the Long Secondary Period in α Orionis
We predict the existence of α Ori B, a low-mass companion orbiting Betelgeuse. This is motivated by the presence of a 2170-day Long Secondary Period (LSP) in Betelgeuse's lightcurve, a periodicity ≈5 times longer than the star's 416 day fundamental radial pulsation mode. While binarity is currently the leading hypothesis for LSPs in general, the LSP and the radial velocity variation observed in Betelgeuse, taken together, necessitate a revision of the prevailing physical picture. The lightcurve-RV phase difference requires a companion to be behind Betelgeuse at the LSP luminosity minimum, 180 degrees out of phase with the system orientation associated with occultation. We demonstrate the consistency of this model with available observational constraints and identify tensions in all other proposed LSP hypotheses. Within this framework, we calculate a mass for α Ori B of 1.17±0.7M⊙ and an orbital separation of 1850±70R⊙, or 2.43+0.21−0.32 times the radius of Betelgeuse. We then describe the features of the companion as constrained by the fundamental parameters of Betelgeuse and its orbital system, and discuss what would be required to confirm the companion's existence observationally.
https://arxiv.org/abs/2408.09089
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