Dramatic Changes Observed in Giant Star WOH G64

Astronomers have observed dramatic changes in one of the largest known stars in the universe, called WOH G64, giving new insight into how massive stars live and die.

WOH G64 is located about 163,000 light-years from Earth in the Large Magellanic Cloud, a nearby galaxy. It is extremely massive—about 28 times the mass of the Sun—and may be up to 1,500 times wider than our Sun.

What makes this star unusual is that it has changed from a cool red supergiant to a much hotter yellow hypergiant over recent years. This kind of transformation is extremely rare and could help scientists understand how giant stars evolve before ending their lives, often in a huge explosion called a supernova.

WOH G64 is also part of a binary system, meaning it has a companion star nearby. The interaction between the two stars and the dust surrounding them may influence the star’s appearance and behavior.

These rapid changes are puzzling because such shifts usually happen over millions of years, yet WOH G64 seems to be evolving much faster. Researchers are closely monitoring the star to determine whether the changes are natural for its stage or influenced by its companion and surrounding dust.

Studying WOH G64 gives astronomers a rare opportunity to watch one of the universe’s largest stars in action as it approaches the end of its life.