A planet may have been destroyed by a white dwarf at the center of a planetary nebula — the first time this has been seen. As described in our latest press release, this would explain a mysterious X-ray signal that astronomers have detected from the Helix Nebula for over 40 years. The Helix is a planetary nebula, a late-stage star like our Sun that has shed its outer layers leaving a small dim star at its center called a white dwarf.