The art of space mission patches is now more than six decades old, dating to the Vostok 6 mission in 1963 that carried Soviet cosmonaut Valentina Tereshkova into low-Earth orbit for nearly three days. The patch for the first female human spaceflight showcased a dove flying above the letters designating the Soviet Union, CCCP.
That patch was not publicly revealed at the time, and the use of specially designed patches was employed only infrequently by subsequent Soviet missions. NASA's first mission patch would not follow for two years, but the practice would prove more sticky for missions in the United States and become a time-honored tradition.
The first NASA flight to produce a mission-specific patch worn by crew members was Gemini 5. It flew in August 1965, carrying astronauts Gordon Cooper and Pete Conrad on an eight-day mission inside a small Gemini spacecraft. At the time, it was the longest spaceflight conducted by anyone.
Robert Pearlman has the story behind the patch at Collect Space, which came about because of the wishes of the crew. During the initial Mercury missions, the pilots were able to name their spacecraft—Freedom 7, Liberty Bell 7, and so on. Cooper had named his Mercury spacecraft 'Faith 7.' But an increasingly buttoned-up NASA ended this practice for the Gemini missions, and when Cooper and Conrad were assigned to the third Gemini flight they considered alternatives.
"Several months before mission, I mentioned to Pete that I'd never been in a military organization that didn't have its own patch," Cooper recounted in Leap of Faith, his memoir. "We decided right then and there that we were at least going to have a patch for our flight."
They chose a covered wagon design to indicate the pioneering nature of the mission and came up with the "8 days or bust" slogan to highlight the extended duration of the flight. Since then, virtually every NASA mission has included a patch design, typically with names of the crew members. The tradition has extended to non-human missions and has generally been adopted by space agencies around the world.