A significant slice of viewers under the age of 40 are unfamiliar with the Minneapolis news producer who once turned the world on with her smile. “Mary Tyler Moore: A Celebration” (7 p.m. Tue., TPT, Ch. 2) introduces the iconic character to a younger generation while providing pangs of nostalgia to those old enough to remember spending Saturday nights in the 1970s comforted by the company of Mary Richards and her makeshift families at WJM News and her Kenwood home.

The documentary is an unspectacular but satisfying pop culture lesson on “The Mary Tyler Moore Show.” Oprah Winfrey, the highest-profile gusher in the one-hour piece, claims she dedicated many of her early years in the business trying to land a job in Minneapolis, if only to follow in the footsteps of her TV idol.

Other participants in the lovefest include Dick Van Dyke, Ed Asner, Valerie Harper, Betty White and Tina Fey. Sorely missing: co-creators James L. Brooks and Allan Burns, who had as much to do with the sitcom’s success as Moore’s spunk.

The clips roll by all too quickly and Moore’s personal struggles are only touched upon, signs that producers should have fought harder for a longer running time and insight from pop culture historians.

“When she came on, it changed America,” co-star Cloris Leachman says.

More perspective and context would have gone a long way to supporting that claim, although woe to any editor who’d dare to present comments from Prof. Know-It-All in place of footage of Richards losing control during Chuckles the Clown’s funeral.