I almost can't remember a time when I wasn't interested in space science. When I was seven or eight years old, I joined the Planetary Society and I collected the mini-posters of planets and moons that came with the magazine. Then my dad went on a business trip to Washington, D.C., and brought back a Voyager 2 poster book he picked up at the Air and Space Museum. I spent almost all of my spare time poring over that book and memorizing the planet and moon facts on the back of each photo. In fact, I used to quiz my family at the dinner table with such questions as which moon was the biggest in the solar system (Jupiter's Ganymede) or which planet had a sideways-rotation axis (Uranus), for example.