Stephen L. Petranek is the author of “How We Will Live on Mars,” from Simon & Schuster, co-published by the TED Conferences. He has been a speaker on the TED main stage three times, and his talks “10 Ways The World Could End Suddenly”  as well as his talk on Mars are among the most popular TED talks of all time, with more than 5 million viewers. He is co-executive producer of National Geographic’s Mars documentary series now in its second season, and also served as science advisor to the series as well as a frequent on-camera  “big thinker.” He was the editor-in-chief of Discover, the world’s largest science magazine, for eight years, and was the editor-in-chief of The Washington Post Magazine for more than a decade. He was sciences senior editor at Life Magazine and the editor-in-chief of Breakthrough Technology Alert, a science-based newsletter for investors. These days he is hard at work on a new book about curing cancer.