Astronauts

An astronaut is a person trained to command, pilot, or serve as crew on spacecraft. Astronauts are trained to operate space vehicles, conduct scientific experiments, and perform tasks such as spacewalks and the operation of robotic arms. They may work on missions that deploy satellites, conduct research, or support long-duration stays on space stations.

Selection and training: Astronaut candidates are selected by national space agencies or by commercial programs and undergo extensive training that typically includes flight theory, space physiology, survival training, simulators, robotics, and long-duration isolation. Training also covers languages, teamwork, and crisis management. Training can last several years and includes time in neutral buoyancy labs, parabolic flights, and underwater analogs to simulate weightlessness.

Roles: Within crews, astronauts may serve as pilots, mission specialists, or payload specialists. They may operate spacecraft, manage experiments, perform spacewalks, operate rendezvous and docking systems, and support in-flight maintenance. Some astronauts later command missions or lead international cooperation efforts.

Terminology: In the Soviet and Russian tradition, cosmonaut is used; in China, taikonaut; in the United States and many other nations, astronaut. International crews on the ISS include members designated by different agencies.

History: Early 1960s: Yuri Gagarin became the first human in space. The US followed with Alan Shepard, John Glenn, and later Apollo missions and Space Shuttle programs. Since the 1990s, astronauts have lived aboard the International Space Station. More recently, private companies have begun training civilian and commercial astronauts.

Outlook: The field continues to evolve with commercial spaceflight, international cooperation, and longer-duration missions to the Moon and beyond.