48 Years Ago Today

Nautilus -- 90 North. The day the nuclear submarine truly proved what it could do. (And still one of only two events for which the crew got to wear a distinguishing device on their Presidential Unit Citation ribbon.)

Molten Eagle had more about this historic achievement last year. Since Molten Eagle asked trivia questions, I guess I can too: What is the other "device" (other than oak leaf clusters and bronze stars for repeat awards) that has been authorized for wear on PUC ribbons? Answers in the comments, please.

Update 0014 03 August: Damn, that was quick. Here's the reference for the answer to the trivia question -- see para AP2.1.2.1.3.2. (For those who want to guess themselves, don't read the comments first.)