List of astronauts by year of selection

This is a list of astronauts by year of selection: people selected to train for a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft. Until recently, astronauts were sponsored and trained exclusively by governments, either by the military or by civilian space agencies. However, with the advent of suborbital flight starting with privately funded SpaceShipOne in 2004, a new category of astronaut was created: the commercial astronaut.

While the term astronaut is sometimes applied to anyone who trains for travels into space—including scientists, politicians, journalists, and tourists—this article lists only professional astronauts, those who have been selected to train as a profession. This includes national space programs and private industry programs which train and/or hire their own professional astronauts.

More than 500 people have trained as astronauts. A list of everyone who has flown in space can be found at List of space travelers by name.