Explained | Will Betelgeuse, the red giant star, blow up in your lifetime? Premium

By examining Betelgeuse’s pulsation – the periodic contraction and expansion of the star – researchers from Japan and Switzerland recently reported that the star is in its late carbon-burning stage. Other researchers have disputed this conclusion and estimated that the star will go supernova only much later.

The bright red star Betelgeuse, called ‘Thiruvathirai’ or ‘Ardra’ in Indian astronomy, is easily spotted in the constellation Orion.

By examining its pulsation – the periodic contraction and expansion of the star – researchers from Japan and Switzerland recently reported that the star is in its late carbon-burning stage. In massive stars like Betelgeuse, the carbon-burning stage lasts only up to a few hundreds of years, after which the star ‘dies’ and collapses into a supernova within a few months.

In humans, slow or abnormal heartbeats indicate a possible blockage of the heart. Likewise, the researchers say Betelgeuse’s observed pulsation matches theoretical estimates from a late carbon-burning stage, suggesting the red supergiant is in its death throes.

“From the pulsation periods, we can infer the radius of the pulsating object. From the calculated radius, luminosity and mass of Betelgeuse, we determine that it must be a late stage of core carbon-burning,” Devesh Nandal, a PhD student in the Department of Astronomy at the University of Geneva and one of the authors of the study, told The Hindu.

A death foretold

Most stars, including our Sun, fuse the simplest element in the universe, hydrogen, to produce helium and some energy as a byproduct. This energy’s outward push balances gravity’s inward pull, and keeps the star from collapsing.

Massive stars like Betelgeuse run out of hydrogen fuel in only a few crore years, when they switch to using helium to make carbon. The energy released in the fusion of helium is less than that of hydrogen, so the star burns more helium to stay stable and not collapse. The helium runs out in about ten lakh years.