I am currently reading the fascinating book "Packing for Mars" by Mary Roach. This book is particularly interesting for me both because it deals with human spaceflight -a particular interest of mine - and because Ms. Roach combines great science writing with a humorous skewed-to-just-this-side-of-demented take on things.
Among the fascinating trivia contained in this book is a discussion of the urine-collection devices used by male space-walkers on the Space Shuttle flights. These devices consist of a condom-like attachment connected to a tube and a urine collection bag. (Restrooms being a scarce commodity outside a spacecraft in low Earth orbit.) These devices come in three sizes. Small, medium and large, you may presume? If so, you presume incorrectly. The three size options are Large, Extra Large and Extra-Extra Large. And, in anticipation of the next question, the answer is no. Astronauts are not more stallion-like than their Earthbound brethren. The reason for the king-sized nomenclature was a concern that those who - for anatomical reasons - required a size "small" would be unwilling to admit that fact and order a larger and thus ill-fitting size with leaky and unpleasant results.
This, however, wasn't always the case. During project Apollo, they did indeed have small, medium and large sized urine collection devices.
In addition, NASA had a seemingly compulsive need to document everything related to the Apollo missions. And I do mean EVERYTHING. Like this list of items left behind on the moon by the Apollo 11 crew. Pay particular attention to items 50 and 51. Four urine collection assemblies were left behind on the lunar surface. Two were large. Two were small. Which leaves one with the obvious speculation. Two astronauts walked on the moon on that lunar morning in July 1969: Neil Armstrong and Buzz Aldrin. One, apparently, was "one giant step" larger in the manhood department than the other. But who was the one with more of the "right stuff"? And how would anyone find out? I suppose someone could simply ask the men involved, but aside from the world-class awkwardness such a query would pose, I doubt either would 'fess up to wearing the size small.
I guess this is one piece of space trivia which must forever remain in the realm of conjecture and debate.