Mike Massimino served as an astronaut for NASA between 1996 and 2014, going on two missions to service the Hubble telescope, spending more than 30 hours on spacewalks. He has appeared as himself on The Big Bang Theory and is now a professor at the University of Columbia. He lives in New York. Tanner Colby is the author and co-author of several books, including the New York Times bestseller The Chris Farley Show. He is a frequent contributor to Slate magazine, and lives in Brooklyn, New York.