One of the largest stars known in the Universe has done something strange – and scientists are debating what it means. WOH G64, a colossal star in the Large Magellanic Cloud, is – or was? – one of the largest red supergiants known, measuring more than 1,500 times the radius of the Sun. In 2013 and 2014, telescopes captured a dramatic transformation, with the star appearing to shift from a classic red supergiant toward a hotter, yellower state. A team of researchers led by Gonzalo Muñoz-Sanchez