Al Markim, known to TV’s first generation of fanboys as Astro, the Venusian pal and fledgling scientist of ’50s sci-fi program Tom Corbett, Space Cadet, died Tuesday, according to his family. He was 88.

After serving in the Army and witnessing the Nuremberg trials of Nazi officials, Markim turned to acting, appearing in the soap opera Love of Life and in an off-Broadway production of La Ronde.

But it was his performance as Astro (at far right in photo) in the pioneering, wildly popular Space Cadet — which aired from 1950 to 1955 and appeared, at one time or another, on all four of the existing networks (CBS, ABC, NBC, DuMont) — that earned him a place in the Boomer pantheon. The series, broadcast live from New York, was a foundational, if decidedly low-tech, excursion into youth culture’s fascination with space, aliens and astronautical derring-do.

By the mid-1960s, Markim had gone behind the camera, serving as an MGM executive in charge of production for Sidney Lumet’s 1964 The Pawnbroker and associate producer of 1965’s The Fool Killer, among others. In 1968, he cofounded Teletronics and, according to his family, later entered into a partnership with Sony, creating the Video Corporation of America, which later merged with Technicolor. He was inducted into the Video Hall of Fame in 1996, and is survived by Sondra, his wife of 53 years; five children and 11 grandchildren.