On this day in the Star Trek universe:

Star Trek (1968)

Star Trek

Season 2. Episode 26.

Episode entitled: Assignment: Earth.

Released March 29, 1968.

Directed by Marc Daniels.

Written by Art Wallace, Gene Roddenberry.

Created by Gene Roddenberry.

Music by Alexander Courage.

Cast: William Shatner, Leonard Nimoy, Nichelle Nichols, DeForest Kelley, James Doohan, George Takei, Majel Barrett, Walter Koenig, Robert Lansing, Teri Garr, Don Keefer, Lincoln Demyan, Morgan Jones, Bruce Mars, Ted Gehring, Paul Baxley, Barbara Babcock, Bill Blackburn, Robert D'Arcy, Frank da Vinci, Rudy Doucette, Roger Holloway, Bob Johnson, Ken Kane, Esther Ying Lee, Eddie Paskey, Edwin Rochelle, April Tatro.