On the Saturday afternoon of July 4, 2015, NASA’s New Horizons Pluto mission leader Alan Stern was in his office near the project Mission Control Center, working, when his cell phone rang. He was aware of the Independence Day holiday but was much more focused on the fact that the date was “Pluto flyby minus 10 days.”... Glancing at his ringing phone, Alan was surprised to see the caller was Glen Fountain, the longtime project manager of New Horizons. He felt a chill because he knew that Glen was taking time off for the holiday, at his nearby home, before...