We can see the moon only once in about a month's time. It is full moon night or "Purnima". A fortnight later, we cannot see it all. It is a new moon night or "Amawasya".
The sun, the moon, and all those objects shining in the night stay are called celestial bodies.
Some celestial bodies are very big and hot. They are made up of gases. They have their own heat and light, which they emit in large amounts. These celestial bodies are called star.
The various pattern formed by different groups of stars are called as constellations.
The North Star indicates the north direction and it is called the pole star.
Some heavenly bodies continue moving around a star. They are called planet. Planet does not have its own particular light. The earth is a planet.
The Eight Planets
The word 'Planet' comes from Greek word "Planetai" which means "Wanders".
All the eight planets of all solar system moves around the sun fixed paths. These paths are called orbit.
Some celestial bodies continue moving around a planet is called satellite. The moon is a satellite off the earth.
The Solar System
The sun, eight planets, satellites and some other celestial bodies known as asteroids and meteoroids from the solar system.
The earth is the third nearest planet to the sun. In size, it is the fifth largest planet. Its shape is described as a "Geoid". The earth is neither too hot nor too cold. It has water and air which are essential for survival.
From the outer surface, the earth appears blue because its two – third surface is covered by water and also called a blue planet.
Moon is the satellite of earth. Its diameter is one one-quarter that of earth. It appears so big because it is nearer to our planet than other. It is about 3, 84,400 km away from us. The moon moves around the earth in about 27 days.
The moon does not favorable for life. It has mountains, plains and depression on its surface.
There are numerous tiny bodies which also move around the sun are called asteroids. They are found between the orbits of mars and Jupiter.
The small pieces of rocks, which move around the sun, are called meteoroids.
A galaxy is a huge system of billions of stars and clouds of dust and gases. These are millions of such galaxies that make the universe.