“That’s one small step for man, one
giant leap for mankind.” Astronaut Neil Armstrong spoke these words on July 20,
1969, as he became the first person ever to step onto the Moon.
An astronaut is a space traveler.
Astronauts fly into space on spaceships. They go where there is no air, higher
than any airplane can fly. While they orbit (go around) Earth, they are
weightless—they float and feel no gravity.
WHO GETS TO BE AN ASTRONAUT?
In Neil Armstrong’s day, all
astronauts were military test pilots. Today, they’re as likely to be medical
doctors, scientists, or engineers. Astronauts are still pretty unusual, however.
Only a few hundred people have ever traveled into space.
Astronauts receive intense
training. Then they may prepare a year or more for a specific mission. Pilots
must be able to control all spacecraft systems and deal with emergencies. They
may need to make course changes or dock with a space station. They must be able
to land the spacecraft. Mission specialists are experts on particular
experiments. Any astronaut may have to perform duties in a space suit outside
the craft.
WHAT DO ASTRONAUTS DO IN SPACE?
Most space missions do not
require human passengers. Robots and computers can do many jobs without needing
people. But astronauts can perform some experiments in space that machines
cannot. They can examine, for example, how flames burn or how crystals grow
without gravity. Some experiments test the effects of spaceflight on human
beings. Astronauts also launch and repair satellites, machines that orbit Earth.
They also retrieve objects in space for return to Earth.
Astronauts may spend weeks or even
months in space. Russian cosmonaut Valeriy Polyakov holds the record for the
most consecutive days in space. He spent 438 days aboard the Mir Space Station
in 1994 and 1995.
THE FIRST ASTRONAUTS
Russian astronauts are called
cosmonauts. The first person in space was cosmonaut Yuri Gagarin. He made
the trip in April 1961. The first American, a month later, was astronaut Alan
Shepard. The first capsules that carried astronauts into space were barely large
enough to hold their single passenger.
FLYING TO THE MOON
The Apollo program began during the
1960s. Apollo was an American project to send people to the Moon and back. There
were three astronauts in each Apollo crew. Two of them explored the Moon while
the third stayed aboard the main spacecraft.
Neil Armstrong, Buzz Aldrin, and
Michael Collins were the crew of Apollo 11. This was the first mission to land
on the Moon. Altogether, 12 astronauts walked on the Moon as part of the Apollo
program. They performed experiments and brought back moon rocks for study. No
one else has ever been to the Moon.
THE SPACE SHUTTLE
During the 1980s, the United
States began to use space shuttles to send astronauts into space. Previously,
spaceships could only fly once. Each trip required a new spaceship. Now, space
shuttles can fly into space many times. They are launched from the top of a
rocket, but they land like an airplane. Up to seven crew members can live aboard
a shuttle.
The United States has begun
research on a new type of reusable spaceship to replace the space shuttle. This
new spaceship will use newer technology and will be cheaper to operate than the
space shuttle. Someday astronauts may walk on the Moon again, or even travel to
other planets!
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