This starts the space race.
Sputnik 2 carried the first living creature into orbit.
Explorer one was the first American satellite to reach orbit. It also led to the discovery of the Van Allen radiation belt,
NASA being formed helped to further the USA in the space race by supplying information and experiments.
Luna 1 was the first man-made object to orbit the Sun.
Luna 2 later impacts the Moon, becoming the first man-made object to do so.
Luna 3 is able to photograph 70% of the Moon's surface, the most thus far.
Tiros 1 was the first successful weather satellite. It got the ball rolling for the satellites we have today that save many lives with their accurate and helpful weather readings.
Gagarin was the first man in space.
Shepard was the first American in space.
Tereshkova was the first woman in space.
Leonov performed the first spacewalk.
Luna 9 was the first spacecraft to soft-land on the Moon.
Luna 10 was the first satellite to orbit the Moon.
Armstrong and Aldrin were the first men to walk on the Moon.