At 4:33 this afternoon, if the weather and all systems are go, a SpaceX-built Falcon 9 rocket, carrying two NASA astronauts in a crew capsule called “Dragon," will lift off from Launchpad 39A at Kennedy Space Center in Florida and soar toward a rendezvous with the International Space Station. The mission, dubbed "Demo 2," will be the first time a privately-built rocket will carry humans into space from US soil, and the first US-built manned spacecraft in a decade. NASA Astronauts Doug Hurley and Bob Behnken, both veterans of multiple missions aboard the now-retired Shuttle Orbiters, will dock the CrewDragon with the International Space Station and remain aboard the ISS for at least several weeks. What will this launch mean for NASA’s bid to send humans back to the Moon by 2024 and to Mars in the coming years, and for the future of commercial space exploration? Tom's first guest is reporter Mike Wall. He has covered the space program for Space.com since 2010, and he's is the author of Out There, a 2018 book about the search for alien life. He joins us via Skype from his home in San Francisco. Then, we get some historical perspectives on the SpaceX launch from esteemed space policy analyst, John M. Logsdon. He’s a Professor Emeritus of political science at George Washington University's Elliott School of International Affairs. In 1987, he founded the Elliott School's Space Policy Institute. Professor Logsdon is also a former member of the NASA Advisory Council and its Exploration Committee. He is the award-winning author of three books about politics and the space program: John F. Kennedy and the Race to the Moon (2010); After Apollo? Richard Nixon and the American Space Program (2015); and Ronald Reagan and the Space Frontier (2019). He has also edited the recently published The Penguin Book of Outer Space Exploration (2018), a collection of original documents tracing the evolution of the U.S. space effort. John Logsdon joins Tom via Skype from his home in Washington, D.C.