A mission specialist (English Mission Specialist ) is a professional function of a NASA astronaut during a space shuttle flight.
A Mission Specialist is responsible for the smooth operations aboard the Space Shuttle and supports the two pilots. While these take care of all issues that have to do with the navigation and control of the orbiter, the mission specialist is entrusted with the flight-specific tasks. So he looked, for example, the scientific experiments on board, leads spacewalks by and is responsible for satellite launches.
Mission specialists are trained by NASA itself and make the most of a shuttle crew. A specially trained mission specialist can be the pilot as a flight engineer on the page. In this role, he helps the commander and the pilot during takeoff and landing in monitoring the instruments and any listed problems with the systems of the shuttle.
Some NASA astronauts who were trained as pilots during their first space flight had the function of a mission specialist.