Riccardo Giacconi

Riccardo Giacconi ( jə-KOH-nee, Italian: [rikˈkardo dʒakˈkoːni]; October 6, 1931 – December 9, 2018) was an Italian-American Nobel Prize-winning astrophysicist who laid down the foundations of X-ray astronomy. He was a professor at the Johns Hopkins University.