Science Lesson

​Stars: We See billions of stars in the night sky . Several group of stars are called Constellations . A system of millions or billions of stars together with gases and dust , held together by gravitational attraction

​is called Galaxy ..

​Blue stars are the hottest , folled by the white stars . Yellow , orange and redstars are the coolest stars in decreasing order of their surface temperatures  . 

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​Sun : The Sun is a Yellow dwarf star and believed to be about 4 billion years old . It spins on its axis . It is part of the Milky Way Galaxy .

​The core of the Sun is Extremely hot and made up of gases. Heat and Light is generated by the Sun . 

​The Solar System :  The Solar System contain eight main planets they are : Mercury, Venus , Earth , Mars , Jupiter , Saturn , Uranus and Neptune .

​These Planets are divided in 2 groups which is :

​Terestrial Planets and Rocky Planets

​1. Mercury 5 Jupiter

​2.Venus 6. Saturn

​3.Earth 7. Uranus

​4.Mars 8 .Neptune

​Jupiter is the largest planet in the Solar System .

Jupiter has 79 moons , but 53 have their official

​The End of the Chapter