Close Encounters With Pluto

In 2015, a spacecraft called New Horizons flew by Pluto at 32,000 miles per hour, taking pictures all along the way. Alan Stern led the planning of the mission for NASA, and he joins us to talk about the years of work that went into sending the New Horizon more than 3 billion miles from Earth. His new book, written with astrobiologist David Grinspoon, is called “Chasing New Horizons: Inside the Epic First Mission to Pluto” (Picador).