Betelgeuse, a giant red star located near the Orion constellation, has always intrigued astronomers with its massive size and light fluctuations. A recent study has shed new light on its seemingly rapid rotation, which contradicts existing theories. This phenomenon is actually an optical illusion caused by turbulent activity on its surface.
Despite its youth, Betelgeuse is already at the end of its life and might soon explode into a supernova, an event that would spectacularly light up our sky.
New simulations show how Betelgeuse's "boiling" surface can ripple as blobs of plasma rise and fall.
Credit: MPA/Ma, Jing-Ze et al
Its rapid rotation, with an observed surface speed of about 11,184 mph (18,000 km/h), has long been a mystery, as it far exceeds expectations for a red supergiant. This puzzle led researchers to reconsider what they had previously interpreted as rotation.
The study, led by Jing-Ze Ma, uses computer simulations to model the surface of Betelgeuse. It reveals that the star is not a perfect sphere, but rather a collection of moving plasma bubbles, similar to a lava lamp. These movements could mistakenly be interpreted as rapid surface rotation when observed through telescopes.
If confirmed by future observations, this theory could not only explain the observed rotation of Betelgeuse but also that of other red supergiants. It marks a significant advance in our understanding of stellar dynamics and could change how we interpret telescope data.
The simulations are very similar to ALMA observations when viewed through a computer program that mimics the telescope.
Credit: MPA/Ma, Jing-Ze et al Betelgeuse: soon to be a supernova
Betelgeuse, one of the brightest and most massive stars in our night sky, is located in the Orion constellation at a relatively short distance of "only" 650 light-years from Earth. It is often cited as an ideal candidate for becoming a supernova in the near cosmic future. This red supergiant is in an advanced stage of its stellar life, having exhausted the hydrogen in its core and burned through heavier elements.
Betelgeuse becoming a supernova is an eagerly anticipated event not only for its visual impact in our sky—it could shine as bright as the full moon and be visible even during the day for several weeks—but also for the unique scientific opportunity to closely study a star's death process.
Betelgeuse is easily visible to the naked eye in the night sky, within the Orion constellation. It is the red star in this image. The large blue star on the opposite side, across from the three stars constituting Orion's belt, is the blue supergiant Rigel.
A star becomes a Type II supernova, which is likely the case for Betelgeuse, when its core, after depleting its nuclear fuel, collapses under its own gravity. This collapse leads to a rapid increase in temperature and pressure, causing a cataclysmic explosion.
The resulting supernova ejects the star's outer layers into space, dispersing heavy elements that were synthesized during the star's life and in the explosion itself. These elements are essential for the formation of new stars, planets, and potentially life forms.
The final stage of Betelgeuse's life before it explodes into a supernova is marked by significant variations in its brightness, phenomena that astronomers are currently observing with great interest. These variations are due to complex processes happening in the star's outer layers, including pulsations and material ejections.
The explosion of Betelgeuse into a supernova will provide a wealth of valuable information about the lives and deaths of massive stars, the nuclear processes occurring within them, and will enhance our understanding of interstellar chemistry. Although astronomers cannot predict precisely when Betelgeuse will become a supernova—it could happen within the next 100,000 years—its ongoing evolution is being closely monitored, as it offers an exceptional opportunity to study such an event up close.