Satellites – JSS1 Basic Science Lesson Note (Third Term)

A satellite is a body that orbits, or moves around, a planet. The moon is a satellite of the Earth. Satellites are either natural, like the moons of the planets, or artificial, meaning man-made bodies launched by countries to orbit the Earth. Artificial satellites are used for observation, weather monitoring, communication, navigation and other purposes.

Behavioural objectives

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

• define a satellite and give an example;
• state the number of satellites of some planets in the solar system;
• distinguish between natural and artificial satellites;
• name some countries and their first satellites;
• list the types of satellites and state their uses.

What is a satellite?

A satellite is a body that orbits or moves around a planet, for example, the moon is a satellite of the Earth.

How many satellites does each planet have?

The satellites or moons of the planets in our solar system are shown below.

What are natural and artificial satellites?

The moons that orbit the planets in the solar system are natural satellites. Artificial satellites are man-made bodies that were launched by various countries and are now orbiting the Earth, for example:

What are the types and uses of satellites?

1. Astronomical satellites: They are used for observation of distant planets, galaxies and other outer space objects.
2. Bio satellites: These are used to carry living organisms, especially for scientific experimentation.
3. Observation satellites: They are used for geographical studies, photographing of areas and map making.
4. Weather satellites: These are used to monitor the weather conditions in the atmosphere and supply the information to ground stations.
5. Communication satellites: They are designed purposely to send information quickly from one place to another.
6. Reconnaissance satellites: They are used for military or intelligence purposes, such as observing enemy location or troop movements.
7. Space station satellites: They are designed for human beings to live on in outer space. They are designed for periods of weeks, months or years.
8. Navigational satellites: These use radio time signals, which enable mobile receivers on the ground to determine their exact location.

Evaluation

1. What is a satellite?
2. Give one example of a natural satellite.
3. What is the difference between a natural satellite and an artificial satellite?
4. Which satellites are used to monitor weather conditions?
5. Name the first satellite launched by Nigeria and the year it was launched.

Assignment

1. List any four types of satellites and state one use of each.
2. Name the first satellite of any three countries in the table above, with the year each was launched.