They are paid according to their military rank. Mission specialists work with pilots to maintain spacecraft and the equipment aboard. They also conduct experiments and launch satellites. In addition, they perform space walks to work outside the spacecraft. A third kind of astronaut is called a payload specialist.
Most payload specialists are scientists who work for the owner of the payload.
In January 1992, she and six other astronauts made an eight-day flight aboard the space shuttle Discovery. During the mission, Bondar studied how space flight affects human beings and how gravity affects and helps shape materials and living things. She experimented with crystals, plants, and insects. She also developed tools and techniques for conducting research in the apparent weightlessness of orbiting spacecraft. Roberta Lynn Bondar was born in Sault Sainte Marie, Ontario.