Timeline Description: Two countries have dominated space exploration: the United States and the Soviet Union. These nations competed in the "space race," or the race to the Moon, which the U.S. eventually won. Even after man first walked on the Moon, fascination with what is in space has continued.
|October 4, 1957||The Soviet Union launches Sputnik 1 into orbit.
Sputnik 1, a man-made satellite, is launched into orbit by the Soviet Union. It was visible from Earth and put pressure on the United States to launch its own satellite.
|January 31, 1958||The United States launches Explorer 1 into orbit.
The satellite Explorer 1 is launched into orbit from Cape Canaveral, Florida. Explorer 1 discovers a radiation belt, the Earth's magnetic field that contains trillions of energy particles from the sun. It is named the Van Allen belt for the scientist who created the experiment.
|April 12, 1961||Yuri Gagarin becomes the first man to be launched into space.
Russian Yuri Gagarin is launched into space on board the spacecraft Vostok 1 and becomes the first man in space. The cosmonaut, as Russian astronauts are called, made one orbit around the Earth.
|February 20, 1962||John Glenn becomes the first American to orbit the Earth.
One of the original seven astronauts of NASA's Mercury program, John Glenn, safely orbits the Earth three times on Friendship 7. Fellow astronaut Scott Carpenter also orbits the Earth three times three months later.
|June 16, 1963||Cosmonaut Valentia Tereshkova becomes the first woman in space.
Russian Valentia Tereshkova becomes the first woman to explore space when she blasts off in Vostok 6. She orbits the Earth 48 times in 71 hours and was chosen from over 400 applicants.
|March 18, 1965||Alexei Leonov becomes the first man to walk in space.
Russian cosmonaut Alexei Leonov leaves his spacecraft and walks in space for 12 minutes. He is the first man to do so and pressure builds on the U.S. to beat the Russians in the "space race."
|January 1967||Three American astronauts die in a fire in Florida.
While testing their spacecraft, a fire breaks out and traps Gus Grissom, Roger Chaffee and Ed White. The American astronauts were part of the Apollo program and were supposed to be on the first manned Apollo mission. All three astronauts die in the testing center in Florida.
|October 11, 1968||Apollo 7 safely completes the first manned mission for the Apollo program.
Americans Wally Schirra, Donn Eisele, and Walter Cunningham make the first successful manned Apollo mission as part of the Apollo 7 flight. They are in space for 10 days and orbit the Earth one time in a spacecraft that has been redesigned since the Apollo 1 tragedy.
|July 20, 1969||Neil Armstrong becomes the first man to walk on the Moon.
With the whole world watching, Apollo 11 astronaut Neil Armstrong lands his spacecraft, "The Eagle," on the Moon. Armstrong is the first man to do this and when he made his first step he said, "That is one small step for man, one giant leap for mankind."
|May 30, 1971||American space orbiter Mariner 9 surveys Mars.
Mariner 9 is the first spacecraft to look at Mars when it orbits the planet less than a month before the Russian Mars 2. Mariner 9 provides over 7,000 photos in the 17 months it is in space.
|May 14, 1973||NASA launches the first space station into space.
Skylab, the first space station, is launched into space and remains in orbit for over six years. The space station is not manned, but astronauts do fly to it for science experiments. Skylab crashes on reentry to Earth and pieces scatter across the Western hemisphere.
|July 20, 1976||NASA lands the first spacecraft on Mars.
Viking 1 becomes the first spacecraft to land on Mars. NASA kept Viking 1 on Mars for six years and collected a wide range of photos and scientific data.
|June 19, 1983||Sally Ride becomes the first American woman in space.
American astronaut Sally Ride blasts into space on the Challenger mission STS-7. She is the first American woman to go into space, 20 years after Soviet cosmonaut Valentia Tereshkova makes her space flight.
|January 28, 1986||American space shuttle Challenger breaks apart in the sky after lift-off.
Seventy-three seconds after lift-off, the space shuttle Challenger explodes and breaks into pieces in the sky. All of the American astronauts on board die as the nation watches the tragedy on television.
|February 1998||The International Space Station is launched into space.
The first piece of the International Space Station is launched into space to provide a place for astronauts from different countries to live and conduct experiments in space. It has remained in space since then and is not supposed to be brought back down until 2020.
|February 2012||Test flights are completed on spacecraft designed to take tourists into space.
SpaceShipTwo, a spacecraft owned by Richard Branson's Virgin Galactic, completes test flights. It is a spaceplane that Branson intends to use to allow tourists to fly into space.