In August and September 1977 the space probes Voyager 1 and 2 started their missions to explore the outer planets of the solar system. Also on board: one gold-plated copper data plate each with analogue image and sound information, including classical and ethnic music, pieces by Chuck Berry and Louis Armstrong, which are intended to provide information about human culture to possible alien discoverers in the distant future. As early as 1971, ELP created a milestone in prog based on Modest Mussorgski's piano cycle, which repeatedly inspired musicians to rework their music with their live album "Pictures At An Exhibition". Famous examples are Maurice Ravel with his orchestral version (1922) or Isao Tomita with his version for electronic instruments (1975). The German fusion project Voyager IV, for its part, was prompted by Keith Emerson to make his own arrangement of Mussorgsky's work. Keyboarder Marcus Schinkel and singer Johannes Kuchta explain the background.