American solar astrophysicist (born 1927) who, in the mid-1950s, developed the theory of the supersonic solar wind and predicted the Parker spiral shape of the solar magnetic field in the outer solar system. Two color glossy 10 x 8 photos of Eugene Parker holding a model of the Parker Solar Probe during a presentation, both signed in black ink, "Best wishes, Eugene Parker." In overall fine condition. NASA renamed its Solar Probe Plus to Parker Solar Probe in Parker's honor, marking the first time NASA had named a spacecraft after a living person.
