Quiz: How well do you know Gustav Holst's 'The Planets'? Classical Music Features Ines Guanchez , Randy Salas · Sep 13, 2018 The planets in our solar system. NASA/JPL Gustav Holst's The Planets celebrates its 100th anniversary this month, with its first complete public performance on Sept. 29, 1918. But how much do you know about this popular orchestral work? Take our quiz to find out!