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

Space travel is the act of going to the moon or planets, or orbiting the Earth, in a special craft called a spaceship. It also means travelling to outer space beyond the Earth. Space travellers are called astronauts. It helps people collect scientific information and improve communication, but it is risky because a failure can cost lives.

Behavioural objectives

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

• explain the meaning of space travel;
• name the three regions outside the Earth’s surface;
• state the characteristics of outer space;
• list the purposes and benefits of space travel;
• 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 special craft called a spaceship. It is also travelling to outer space beyond the Earth.

Space travellers are called astronauts. On the 21st of July, 1969, Neil Armstrong, an American, became the first human being to step onto the moon. He was followed on the same day by another American named Edwin Aldrin. They stayed on the moon for 21 hours 36 minutes before they lifted off.

The last moon landing of the Apollo programme took place in December 1972. Two Americans, Eugene Cernan and Harrison Schmitt, stayed a total of 74 hours and 59 minutes on the moon’s surface. These astronauts wore special protective uniforms with oxygen masks for breathing.

Most experiments in space are currently carried out in space stations or space labs. These space stations are very large spacecraft that can accommodate many people and are equipped to perform scientific experiments. Astronauts who work on these space stations usually stay for a period of six months to one year, after which they are replaced by other astronauts.

The spaceship is moved by rockets. After the spaceship leaves the Earth’s atmosphere, gravity no longer pulls it to the Earth. The astronauts wear special suits, which help them to maintain the Earth’s atmospheric pressure around their bodies throughout space.

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

Space refers to the region of our environment outside the Earth’s crust. There are three important regions outside the Earth’s surface. These are:

1. The troposphere: It starts from the surface of the Earth and extends to a height of about 16,000 metres. Most of the air and water vapour in our environment are found in this region. As one goes up in the troposphere, the temperature falls, so it becomes cooler.
2. The stratosphere: It is the region directly above the troposphere. The region contains very little air. The temperature of this region does not fall as one goes up.
3. The ionosphere: It is the upper part of the atmosphere. It contains mainly charged particles. The ionosphere is very useful to man because it enables the reflection and transmission of radio waves and signals around the world.

What are the characteristics of outer space?

1. Light from the sun passes through outer space.
2. There is no force of gravity in outer space.
3. Outer space is void or empty.
4. Sound does not pass through outer space, therefore outer space is always quiet.
5. Outer space is very large and beyond our imagination.

What is the purpose of space travel?

1. It helps us to watch everything that is happening in the world on television, for example football games and basketball games, at the same time as the events are taking place.
2. Space exploration is the use of astronomy and space technology to study outer space.
3. Space travel comes from man’s curiosity, which is a desire to find out the nature of life on other planets.
4. The need for more knowledge of the climate and vegetation of the Earth is another reason for space travel.
5. The landing of equipment called satellites in space has also led to the improvement in communication.

What are the benefits of space travel?

1. The main benefit is the collection of scientific information about the Earth and the other planets.
2. Production of special computers.
3. Production of photographic equipment such as X-ray and gamma-ray equipment.
4. Production of telecommunication equipment.
5. Production of remote sensing equipment to guide spacecraft, for example rockets.
6. Production of rocket or aircraft fuels.

What are the dangers of space travel?

Space travel is risky. If anything goes wrong, one or more lives will be lost.

The dangers of space travel can be caused by the following:

1. Explosion of rockets at the launch pad.
2. Failure of some necessary equipment in the spaceship to function well.
3. Inability of the rocket to reach escape velocity.
4. Wrong calculation of angle, speed and time of launching.
5. Explosion of rockets in flight.

What are the problems of space travel?

1. High speed: Astronauts have to be trained to adapt to the high speed of space travel so that they can think and work normally while travelling in space.
2. Complicated calculation: There are a lot of calculations involved before a spaceship can be launched correctly at an angle, speed and time to arrive at its destination. This is because the Earth, the moon and all the planets are always in rapid motion.
3. Loss of weight: The force of gravity is not felt in space, so it is very difficult for astronauts to stand or walk as they do on Earth.
4. Lack of basic needs of life: The basic needs of life such as water, oxygen and food are not available in space. Oxygen and water must therefore be made available in the spaceship to last for the period of the trip.
5. Escape velocity: Rockets require escape velocity to escape from the attraction of the Earth or the force of gravity.
6. Force of gravity: The force of gravity makes it difficult for any spacecraft to escape the Earth’s surface easily. The spacecraft has to reach a very high speed before it can leave the Earth’s surface.

Evaluation

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

Assignment

1. Who was the first human being to step onto the moon, and on what date did this happen?
2. State three characteristics of outer space.
3. Explain any two problems astronauts face in space travel.