Astronomers Observe Rapid Transformation of Massive Star WOH G64

WOH G64, a massive star located approximately 160,000 light-years away in the Large Magellanic Cloud, has exhibited a rapid transformation from a red supergiant to a yellow hypergiant, according to recent observations. This change, occurring over a few years, challenges existing models of stellar evolution.

In 2014, astronomers noted a significant increase in the star's surface temperature, leading to a color shift from red to yellow. This transition was not accompanied by any eruption or explosion, making it particularly unusual. Gonzalo Muñoz-Sánchez, lead author of the study published in Nature Astronomy, stated,

"Typically the evolution of a star takes place on timescales of billions of years. On human timescales, we only observe more abrupt and violent events, such as eruptions, the merger of two stars or their explosive deaths."

WOH G64 is approximately 28 times the mass of the Sun, with a luminosity about 300,000 times greater and a diameter roughly 1,500 times larger. If positioned at the center of our solar system, its surface would extend between the orbits of Jupiter and Saturn. The star is estimated to be around 10 million years old, nearing the end of its lifespan.

The rapid transformation of WOH G64 provides a unique opportunity to study the late stages of massive star evolution. Muñoz-Sánchez noted,

"No current stellar models can fully explain this transformation."

Further research is needed to understand the mechanisms driving such rapid changes in massive stars.