Sputnik 1, the first human-made satellite, was launched on October 4, 1957, marking the beginning of the space age.
On April 12, 1961, cosmonaut Yury A. Gagarin made history as the first human in space and was in the Earth's orbit aboard the Vostok 1 spacecraft for 1 hour and 29 minutes.
The historic Apollo 11 mission, launching Neil Armstrong, Edwin E. Aldrin Jr., and Michael Collins towards the Moon on July 20, 1969, is remembered as a giant leap for mankind.
On April 25, 1990, the space shuttle Discovery deployed the Hubble Space Telescope into orbit. Named after astronomer Edwin Powell Hubble, the telescope was the most advanced optical observatory ever placed in space.
On June 21, 2004, SpaceShipOne became the first privately built manned spacecraft to cross the boundary of space. The flight marked a historic milestone, making Mike Melvill the first commercial astronaut-pilot.