​1. What are your favorite space movies? Apollo 13, The Right Stuff, and The Martian, which Mark saw twice. It nailed how astronauts use science to solve problems and how Earth- and space-bound crews relate, he says.

​2. Who would play you in the movie The Kelly Brothers, Space Twins? Vin Diesel.

​3. Who would play your twin brother, Scott? Vin Diesel.

​4. How can the ASAE audience tell you two apart? Since Mark shaved his mustache, it’s not easy. But their name tags will help.

​5. Will you ever achieve your childhood dream of flying in a rocket ship with your brother? “Unlikely”—since both are retired from NASA now—“but not impossible”—given the potential of space tourism. Mark is part of that burgeoning industry as director of flight crew operations at World View, a “near-space tourism company.” The company plans to let passengers travel up to 100,000 feet above the Earth in a capsule hoisted by a helium balloon.

​6. Is it true that your high school ambition was to be the first man on Mars? Yes, although unfortunately, “I was born just a little too early. But I predict that the person who will do it—maybe still a little kid or maybe even someone in his or her 20s—is alive today.”

​7. Do you believe there’s life elsewhere in the universe? “It’s a big universe, and there’s probably life all over it. But can that life build spaceships as we understand them and travel here? Given the distances, and the speed at which they’d have to travel, should we expect to see them hovering over us, like the spacecraft we used to hear about over Roswell, New Mexico? Probably not.”

(Official NASA photo)