In 1961, Yuri Gagarin became the first human in space. Since that historic milestone, many more astronauts have followed.

For more than half a century, men and women have lived and worked in space to learn more about the Earth and our solar system, and to study the effects of zero gravity on the human body. Now, astronauts are preparing for humanity’s next giant leap – a return to the Moon and a push to Mars.

In today’s photo gallery, take a look back at some of these brave explorers who have boldly traveled into space for the good of all humankind, and don’t forget to learn more about them in our International Space Station Gallery during your next visit!

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