1. What is the shape of the earth?
The Earth is shaped like an orange. It is like a ball that is flattened at the top and bottom. This shape is called geoid. Geoid means 'earth-shaped'.
2. What does the universe consist of ?
The stars, planets, and other heavenly bodies make up the universe.
3. What are stars?
Stars are large balls of fire that give out heat and light.
4. Describe the solar system.
We live on a planet called the Earth. The Earth goes around a star called the sun. The sun is at the centre of the solar system. There are eight planets in the solar system. They are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
All the eight planets go around the sun in a regular, fixed path called orbit. They move at different speeds, in different directions, and spin in different ways.
Mercury, Venus, Earth and Mars are called the inner planets. Jupiter, Saturn, Uranus and Neptune are the outer planets.
Mercury is closest to the sun but Venus is hotter. Venus has a thick blanket of gases surrounding it, which traps the heat in, like an oven. So it is hotter than Mercury.
Jupiter is the biggest planet and Mars is the red planet.
5. Why is there life on the Earth?
The Earth is the only known planet that has life. Life is possible on the Earth as it has water and air. There is more water on the Earth than land. Air and water are both necessary for life.
6. What is rotation?
Each planet also spins around its axis. The axis is an imaginary line around which a planet spins. This spinning movement is called rotation.
7. Define revolution?
All planets move in their fixed paths or orbits around the sun. This movement of the planets around the sun is called revolution.
8. Define Astronomy.
The study of stars is called astronomy.
9. What is a satellite?
Satellites are heavenly bodies that move around, or orbit, a planet. They do not have light of their own. Our Earth's natural satellite is the moon. It reflects the light of the sun.
Name the following.
1. The hottest planet.
2. The red planet.
3. The Portuguese sailor who first showed that the Earth is round.
4. Name the Earth's natural satellite.