Photo: IMDB.com

It was the kiss heard around the galaxy.

Fifty years ago, two of science fiction's most enduring characters, Captain James T. Kirk and Lieutenant Nyota Uhura, kissed each other on "Star Trek," one of the first interracial kisses on television.

The kiss between William Shatner and Nichelle Nichols made an early statement about the coming acceptance of interracial relationships in a United States still struggling with racism and civil rights.

The episode "Plato's Stepchildren" first aired on Nov. 22, 1968. Despite worries about Southern racism, the kiss was broadcast without much blowback.

In a 2010 interview, Nichols said "Plato's Stepchildren" got the most "fan mail that Paramount had ever gotten on Star Trek for one episode."

The episode aired only a year after the U.S. Supreme Court made interracial marriage legal nationwide.