Crew members of STS-51L mission walk out of the Operations and Checkout Building on their way to Pad 39B where they will board the Space Shuttle Challenger. From front to back: Commander Francis R. "Dick" Scobee; Mission Specialists Judith A. Resnik and Ronald E. McNair; Pilot Michael J. Smith; Payload specialist Christa McAuliffe; Mission Specialist Ellison Onizuka; and Payload specialist Gregory Jarvis.