The red supergiant Betelgeuse, more than 650 light-years from Earth, is approaching its inevitable end. Researchers from Tohoku University in Japan and the University of Geneva in Switzerland conducted a new study that reevaluated the fluctuating brightness of this star and concluded that it is in the last phase of its life.
Betelgeuse, one of the most famous stars in the night sky, has long attracted the attention of astronomers. In 2019, it suddenly faded, causing concern among scientists. This year, however, the star glowed brighter than usual again, prompting new speculation about its fate.
Betelgeuse is a red supergiant that appeared just 10 million years ago. It is now a swollen red ball of gas, nearing the exhaustion of its fuel. The question of how long this star will last depends on several factors.
One of these factors is the size of the star itself. Throughout the 20th century, scientists debated the exact size of Betelgeuse. However, recent measurements indicate that the star is in a more compact state, which means that it could still have many tens of thousands of years before it becomes cold enough to explode.
In addition, the fluctuations in Betelgeuse’s brightness are related to the star’s internal dynamics. Its outer layers pulsate in an equilibrium between compression and expansion caused by competing pressures and gravity. These oscillations occur at specific frequencies that repeat over months or even years. Betelgeuse has the two most noticeable oscillation periods, approximately 2,200 and 420 days.
Previously, the shorter period was thought to be the primary period for this star. However, a new study confirms the possibility of a longer pulse, which is related to the star’s thermodynamics. If Betelgeuse compresses atomic nuclei into larger elements, such as carbon, this could lead to a longer radial pulse period. The research team demonstrated that a longer pulse would correspond to a larger radius of the star.
Thus, Betelgeuse may still have some time before its end. However, scientists continue to study this star and observe its changes to better understand its fate.
