Humans have been traveling to space for over 60 years. Our journey officially began on October 4, 1957. On this day, the Soviet Union became the first country to send a human-made satellite into Earth's orbit.

The Soviet Union was a large group of countries that included Russia. Its satellite was named Sputnik. A satellite is an object that orbits, or circles, a planet, moon, or star. Sputnik orbited Earth. It made one full trip around every 96 minutes.

A month after the Sputnik launch, the Soviet Union launched Sputnik II. This was an even bigger accomplishment because Sputnik II carried the first living creature into space. It was a dog named Laika.

A Race to Space

For years, the United States and Soviet Union had been competing to develop satellites. The countries were not getting along at this time in history. The conflict was known as the Cold War. There were no battles. It was mostly a war of threats. Still, the United States was worried. They were falling behind in the race into space.

The U.S. had been working on its own satellite before the launch of Sputnik. There were two failed attempts. Then, finally, the U.S. had success. It launched the Explorer satellite in 1958. Explorer carried scientific instruments, one of which was a Geiger counter. This tool allowed the U.S. to study high-energy rays in space. The rays reach our solar system from faraway stars and galaxies.

In the late 1950s, the United States created a government group to run the space program. It is called the National Aeronautics and Space Administration, or NASA.

The Soviets Met Many Space Goals First

Meanwhile, Soviet successes continued. The first human in space was a Soviet named Yuri Gagarin. He made one orbit around Earth on April 12, 1961. His flight lasted 108 minutes. About three weeks later, NASA launched astronaut Alan Shepard into space. His spacecraft did not go all the way around Earth, though. The flight lasted just 15 minutes.

The Soviet Union met several space goals ahead of the United States. The Soviets launched the first satellite, first dog and first human into space. They achieved the first spacewalk. This was the first time a person stepped outside of a spacecraft in space. They also sent the first woman astronaut into space.

The U.S. Launches Forward

In 1961, American President John F. Kennedy gave NASA a challenge. He wanted the U.S. to put a man on the moon before 1970.

NASA worked hard to meet this challenge. They developed Project Gemini. Astronauts tested what would be needed for a flight to the moon.

Project Apollo followed Project Gemini. Apollo took astronauts into orbit around the moon. Then it took them to the moon's surface. In 1969, on the Apollo 11 mission, Neil Armstrong became the first human to step on the moon's surface. NASA had met President Kennedy's challenge. NASA would land humans on the moon five more times. During these missions, astronauts collected samples of rocks and dust that scientists still study today.

During the 1960s and 1970s, NASA also launched a series of space probes. Space probes do not have human pilots. They are robotic spacecraft that explore space. These probes studied the planets Venus, Mars, and Mercury.

Probes Help Scientists Find Planets

Space stations were the next step in exploring space. The first space station was the Soviet Salyut 1 station. This was launched in 1971. Then NASA launched the Skylab space station. Skylab was the first laboratory where astronauts and scientists studied Earth. Today, astronauts do research on the International Space Station. It's like a science lab orbiting Earth. Astronauts from many countries work together there.

The Apollo Moon program ended in 1972. Much of today's space exploring is done by probes. Probes have made many discoveries. They have taken photos of the surface of Mars. They have even discovered oceans underneath the surface ice of one of Jupiter's moons. Scientists think these oceans may contain life.

Other instruments in space do important work too. One example is the Kepler Space Telescope. Now retired, this space telescope has discovered thousands of exoplanets. These are planets outside of our solar system.