Space Travel – JSS1 Basic Science Lesson Note (Third Term)

Space travel is the journey of people or machines beyond the Earth’s surface, to the moon, to other planets or into orbit around the Earth, in a craft called a spaceship.

Behavioural objectives

By the end of the lesson, students should be able to:

1. explain the meaning of space travel;
2. name the three regions outside the Earth’s surface;
3. state the characteristics of outer space;
4. list the purposes and benefits of space travel;
5. state the dangers and problems of space travel.

What is space travel?

Space travel is the act of going to the moon or planets, or orbiting the Earth, in a spaceship.

• Astronaut: a person trained to travel and work in space.
• Spaceship: a special craft built to carry people or equipment into space.
• Rocket: the engine system that pushes the spaceship away from the Earth.
• Space suit: a protective suit that keeps air pressure around the astronaut’s body, with oxygen for breathing.
• Space station: a very large spacecraft in orbit where many people live and carry out experiments.

Who were the first people to land on the moon?

Neil Armstrong, an American, was the first human being to step onto the moon, on 21st July 1969.

• Edwin Aldrin: another American, who followed Armstrong onto the moon on the same day.
• Time on the moon: Armstrong and Aldrin stayed 21 hours 36 minutes before they lifted off.
• Last Apollo landing: it took place in December 1972.
• Eugene Cernan and Harrison Schmitt: two Americans who stayed 74 hours 59 minutes on the moon’s surface during that landing.
• Protective wear: all the moon walkers wore special uniforms with oxygen masks for breathing.

What is a space station?

A space station is a very large spacecraft that stays in orbit and is equipped for scientific experiments.

• Space lab: another name for a space station used for experiments.
• Capacity: it can hold many people at the same time.
• Stay of astronauts: astronauts usually stay for about six months to one year, then other astronauts replace them.
• Work done: most experiments in space are carried out in space stations.

How does a spaceship leave the Earth?

A spaceship leaves the Earth when rockets push it fast enough to overcome the pull of the Earth’s gravity.

1. The rockets are fired and push the spaceship upwards.
2. The spaceship must reach escape velocity, the speed needed to leave the pull of the Earth.
3. The spaceship passes through the layers of the atmosphere into outer space.
4. Astronauts wear space suits to keep the Earth’s air pressure around their bodies.

What is space and what are the regions outside the Earth’s surface?

Space is the region of our environment outside the Earth’s crust, and it has three important regions: the troposphere, the stratosphere and the ionosphere.

The three regions compared

Why is the ionosphere useful?

• Radio waves: it reflects them back to the Earth.
• Communication: it helps signals travel long distances around the world.

What are the characteristics of outer space?

Outer space is the huge, almost empty region beyond the Earth’s atmosphere.

• Sunlight: light from the sun passes through outer space.
• Very weak gravity: astronauts in orbit feel weightless because they are falling around the Earth, not because gravity is absent.
• Empty: it is almost a vacuum, with no air.
• Silent: sound cannot pass through it, so it is always quiet.
• Very large: it is beyond our imagination.

What is the purpose of space travel?

The purpose of space travel is to learn about the Earth and outer space and to improve life on Earth.

• Live broadcasts: satellites help us watch events such as football and basketball games on television as they happen.
• Space science: astronomy and space technology are used to study outer space.
• Curiosity: people want to find out the nature of life on other planets.
• Study of the Earth: scientists need more knowledge of the Earth’s climate and vegetation.
• Communication: satellites placed in orbit have improved communication.

What are the benefits of space travel?

The main benefit of space travel is the collection of scientific information about the Earth and other planets.

• Special computers: their production has grown from space research.
• Photographic equipment: examples are X-ray and gamma-ray equipment.
• Telecommunication equipment: it supports phone, radio and television links.
• Remote sensing equipment: it helps to guide spacecraft such as rockets.
• Fuels: better rocket and aircraft fuels are produced.

What are the dangers of space travel?

Space travel is risky because a failure can cost the lives of one or more astronauts.

• Explosion at the launch pad: the rocket blows up before take-off.
• Equipment failure: some necessary equipment in the spaceship does not work well.
• Escape velocity not reached: the rocket cannot leave the pull of the Earth.
• Wrong calculation: the angle, speed or time of launching is worked out wrongly.
• Explosion in flight: the rocket blows up after take-off.

What are the problems of space travel?

The problems of space travel are the difficulties that scientists and astronauts must solve before and during a trip.

• High speed: astronauts are trained to think and work normally at the high speed of space travel.
• Complicated calculation: the angle, speed and time of launch must be exact, because the Earth, the moon and the planets are always moving.
• Weightlessness: astronauts in orbit feel no weight, so standing or walking as on Earth is very difficult.
• Lack of basic needs: water, oxygen and food are not available in space, so enough must be carried for the whole trip.
• Escape velocity: a rocket must reach a very high speed to break away from the Earth’s gravity.

Evaluation

1. What is space travel?
2. What is space?
3. Mention the three regions of space.
4. State five dangers of space travel.
5. State three characteristics of outer space.

Assignment

Write a short answer that names the first human being to step onto the moon, gives the date, and explains any two problems astronauts face in space travel.