One of the brightest stars in the northern sky – a source of many surprises. A new study suggests that the extreme rotation of the giant Betelgeuse may actually be an optical illusion.
Betelgeuse in the constellation of Orion is one of the brightest stars in the northern sky. In the past, there have been many speculations about this red giant, including the possibility that it may explode as a supernova in the near future.
In any case, it is a huge star, about a thousand times larger than the Sun, which has reached the end of its life cycle. This is consistent with the extreme manifestations we observe in this star. It sheds a lot of mass and rapidly changes its brightness. Previous observations with ALMA also showed that Betelgeuse rotates rapidly – estimated to be up to 5 km/s, much faster than we would expect for such a star.
Boiling giant
In a study published in the peer-reviewed journal Astrophysical Journal Letters, astrophysicist Jin-Ze Ma from the German Max Planck Institute and his colleagues propose another explanation for the strange behavior of the red supergiant. According to the scientists, the reason for Betelgeuse’s rapid rotation lies in its fiercely boiling surface.
Compared to the relatively calm and quiet Sun, Betelgeuse’s surface looks as if it is boiling fiercely all over. When a large bubble appears on one side of the giant and disappears on the other, it may seem in radio images that Betelgeuse is spinning frantically. But in reality, this is most likely not the case. Although Ma’s team’s conclusions that the extreme rotation speed is just the result of an optical illusion cannot be considered final, they are supported by hydrodynamic modeling results.