Astrophysicist Yaël Nazé of the University of Liège in Belgium has solved the mystery of a giant star, Gamma Cassiopeia (γ Cas), for 50 years. The X-ray emissions from the massive blue star are not from the star at all, but from a tiny, invisible white dwarf siphoning material from its larger companion, heating it to extreme temperatures as it falls in. The system, which consists of multiple stars, is located 550 light-years away in the constellation of Cassoopeia. The discovery was made thanks to high-precision observations of the X-Ray Imaging and Spectroscopy Mission (XRISM). These data also revealed that the plasma from the white dwarf was associated with the compact companion, not with the star itself.