US astronauts have traditionally worn emblems/insignia, or crew patches, on their flight suits. The Mercury astronauts wore only the NASA logo. There were no official emblems for each flight. But the astronauts personalized their missions by naming their space capsules: Freedom 7, Liberty Bell 7, Friendship 7, Aurora 7, Sigma 7 and Faith 7 for Mercury missions 3, 4, 6, 7, 8 and 9 respectively. The '7' refers to the Original 7 astronauts. The next manned flight programme, Gemini, had its own emblem. But there were no official crew patches for the first two missions, Gemini 3 and 4, although there were commemorative ones designed. From Gemini 5, however, official patches were designed and worn by the astronauts. The tradition has continued to the present day and has led to an interesting art form. Each crew has a say in the final design of the patch, which reflects the mission objectives and often their beliefs and aspirations.
Since the Challenger disaster, when seven astronauts died, many patches feature seven commemorative stars. The American flag and eagle are also common themes.
