Astronauten
William E. Thornton
National Aeronautics and Space Administration
William F. Readdy
National Aeronautics and Space Administration
William Frederick Fisher
National Aeronautics and Space Administration
William G. Gregory
National Aeronautics and Space Administration
William H. Dana
National Aeronautics and Space Administration
William H. Lewis
Blue Origin
William J. Knight
National Aeronautics and Space Administration
William Oefelein
National Aeronautics and Space Administration
William R. Pogue
National Aeronautics and Space Administration
William S. McArthur
National Aeronautics and Space Administration
William Shatner
Blue Origin
William Shepherd
National Aeronautics and Space Administration
Winston E. Scott
National Aeronautics and Space Administration
Wu Fei
China National Space Administration
Wubbo Ockels
European Space Agency
Yang Liwei
China National Space Administration
Ye Guangfu
China National Space Administration
Yelena Kondakova
Russian Federal Space Agency (ROSCOSMOS)
Yelena Serova
Russian Federal Space Agency (ROSCOSMOS)
Yevgeny Khrunov
Russian Federal Space Agency (ROSCOSMOS)
Yi So-yeon
Korean Astronaut Program
Yozo Hirano
Space Adventures
Yulia Peresild
Russian Federal Space Agency (ROSCOSMOS)
Yuri Baturin
Russian Federal Space Agency (ROSCOSMOS)