Scott Joseph Kelly is an engineer, retired American astronaut, and a retired U.S. Navy Captain. A veteran of four space flights, Kelly commanded the International Space Station on Expeditions 26, 45, and 46.
John Gerard "Johnny" Brennan is an American actor, film writer, and voice actor. Johnny Brennan is the creator of the Jerky Boys.
Carl Zimmer is a popular science writer and blogger who has specialized in the topics of evolution and parasites. He has authored many books and contributes science essays to publications such as The New York Times, Discover, and National Geographic.