Space Shuttle Challenger disaster cause to the accident. After the accident, NASA attempted to aim at a more realistic shuttle flight rate: it added another orbiter, "Endeavour", to the space shuttle fleet to replace "Challenger", and it worked with the Department of Defense to put more satellites in orbit using expendable launch vehicles rather than the shuttle. In August 1986, President Reagan also announced that the shuttle would no longer carry commercial satellite payloads. After a 32-month hiatus, the next shuttle mission, STS-26, was launched on September 29, 1988. Although changes were made by NASA after the "Challenger" accident, many commentators have argued that
Space Shuttle Mission 2007 Space Shuttle guiding the user through the mission. Extra-vehicular activities are conducted in first-person view allowing the user to experience the same feeling as astronauts do while "space walking". In certain missions, the virtual astronauts will also drive the Manned Maneuvering Unit to capture satellites for maintenance. The latest mission add-on is the STS-47 Spacelab mission. In this mission, the user can visit the Spacelab-J and float inside the lab in Zero-G just like real astronauts. Space Shuttle Mission 2007 Space Shuttle Mission 2007, is a highly realistic Space Shuttle stand-alone mission simulator for Microsoft Windows. The simulator was released