“Then it’s time to don a triangular yellow plastic urine bag by inserting the penis into a rubber receiver built into one corner of it. There are three sizes of receivers (small, medium, large), which are always referred to in more heroic terms: extra large, immense, and unbelievable. One selects based on bitter experience in ground tests, where a poor fit in the feet-above-head Gemini seating arrangement means urine trickling up the spine and pooling in the small of the back. “Wetbacks,” the suit technicians call these neophyte astronauts, with displeasure.”