The left side of the watch is where the "launch aperture" displays three critical phases of the space shuttle's launch sequence. The green phase represents the period shortly after the shuttle is processed for flight. This is when the final pre-flight checks occur, and the decision
link to launch is made by processing weather information from The National Weather Service,
link who operate the Spaceflight Meteorology Group. Input is also considered from
link the U.S. Air Force's 45th Weather Squadron.