That would be the MMUs, Manned Maneuvering Units. To my surprise, there was a docent on the train, Shirley Prutch, who knew a great deal about them. Her remarks as people came on board were spirited (“…we were not only going to the moon, we were going to land on the moon, and we were going to return from the moon, and yes, we were going to do it before Russia…”). Turns out that Prutch had headed the division “at Martin” that developed the software for the maneuvering units. (“My dad worked for Martin before I did,” she told me, “and I don’t say ‘Martin Marietta’ or ‘Lockheed Martin’; it’ll always just be Martin to me.”) With the help of two paintings portraying extravehicular activity—“Working in Space” by Linda Draper and “Premiere Flight of Endeavour” by Howard Koslow—she explained to me how the MMUs worked. I realized then that the “Artistry of Space” exhibit would probably reach a lot of the people who had worked in the space program and that, like Prutch, they would see the art, remember their careers, and explain what they did to friends and neighbors, all across the country.