For decades, astronomers have been watching WOH G64, an enormous heavyweight star in the Large Magellanic Cloud, a galaxy visible with the naked eye from the Southern Hemisphere. This star is more than 1,500 times larger than the Sun and emitting over 100,000 times more energy. For a long time, red supergiant WOH G64 looked like a star steadily reaching the end of its life, shedding material and swelling in size as it began to run out of fuel.
Astronomers didn’t think its final demise would happen anytime soon, because no-one has ever seen a known red supergiant die. But in recent years astronomers – including our team working with the Southern African Large Telescope (SALT) – discovered that this star has started to change, growing dimmer than before and seemingly warmer. This has surprised scientists and suggests the star’s final stages of life may be more complicated, and perhaps unfold faster, than once thought.
Massive stars, more than about eight times the mass of the Sun, produce so much energy, which we see as light, that they run out of fuel within millions of years, instead of the billions of years of the Sun’s lifespan.
