Geo Ch 1 The Earth and solar system .pptx

for primary children

1. The Earth and the Solar System.

2. All objects, which we see in the sky are called HEAVENLY BODIES or CELESTIAL BODIES A COLLECTION OF HEAVENLY BODIES , LIKE THE SUN,THE EIGHT PLANETS AND THE MOON

3. The Universe has countless number of galaxies Our Sun and all the stars belong to a galaxy, it is called Milky Way Galaxy or the Akash Ganga

4. Astronomers do not use ordinary units of measurement such as K.M and miles to measure the distance between heavenly bodies They normally use a unit of measurement called the LIGHT YEAR

5. What is Light Year A light year is the distance travelled by light in one year The speed of the light is 3 Lakh K.M per second Thus light travels a distance of about 9 Lakh 50 thousand cr. Km in one year

6. The stars are huge bodies made up of hot gases They have their own heat and light, they twinkle at night The stars are formed from the clouds of gas and dust in space, which is called NEBULA The nearest star to the earth, apart from the sun is PROXIMA CENTAURI

7. THE SOLAR SYSTEM The family of the sun is known as the Solar system The solar system is a part of the Milky Way galaxy

8. THE SUN THE SUN IS A HUGE BALL OF FIRE MADE UP OF HYDROGEN AND HELIUM.THE SUN IS THE SOURCE OF ALL HEAT AND ENERGY . The sun is at an average distance of about 15 cr km from the earth.

9. PLANETS PLANETS ARE NON-LUMINIOUS BODIES. THEY ROTATE ON THEIR OWN AXIS AND REVOLVE AROUND THE SUN.

10. EIGHT PLANETS Mercury Venus Earth MARS Jupiter Saturn Uranus Neptune

11. Inner Planets Mercury, Venus, Earth and Mars are inner planets These planets are close to the sun and made up of rocks. They are also called terrestrial planets that is earth like planets Outer Planets Jupiter, Saturn, Uranus and Neptune are outer planets They are called gas giants

12. The Satellites The word satellite means an attendant or a companion There are more than 100 known satellites in the solar system Mercury and Venus are the only planets which do not have any known satellites

13. THE UNIQUE PLANET- EARTH THE EARTH IS THE ONLY PLANET WHERE LIFE IS POSSIBLE. DUE TO THE AVAILABILITY OF AIR,WATER AND ITS DISTANCE FROM THE SUN . Earth looked in blue in color due to the presence of water. Earth is also called the watery planet or the blue planet

14. THE MOON THE MOON IS THE EARTH’S ONLY NATURAL SATELLITE. THE MOON IS ABOUT 384,400 KMS AWAY FROM THE EARTH . No life can exist on the moon due to the absence of atmosphere and moisture

15. Two American astronauts, Neil Armstrong and Edwin Aldrin landed on the moon on 21 July 1969

16. PHASES OF THE MOON. Moon reflects the light of the sun The journey from new moon to full moon the visible portion increases and the moon is said to waxing The journey from full moon to new moon the visible portion decreases and the moon is said to waning

17. Waxing Waning Vedeo

18. ASTEROIDS ASTEROIDS are small planet like solid objects found in the solar system They are also called planetoids or minor planets Billions of asteroids lies between the orbits of Mars and Jupiter

19. METEORS Also known as shooting stars Meteors are small pieces of rocks revolving around the sun Most of them burn up and become gases Some are not burnt up completely and hit the surface of the earth, they are called meteorites

20. METEORIT E S Meteor Crater in Arizona state in USA

21. COMETS COMETS are huge lumps of snow and rocky dust When comets reach near the sun, they start glowing and develop a long tail The most famous comet is Halley's comet

22. CONSTELLATION A GROUP OF STARS FORMING VARIOUS SHAPES IS CALLED CONSTELLATION . The most easily recognizable constellation is the SAPTHARISHI , which is a group of seven stars .

23. THE END

24. ASTEROIDS THE NUMEROUS TINY BODIES , WHICH REVOLVE ROUND THE SUN.THESE BODIES ARE CALLED ASTEROIDS.

25. Mercury and Venus Mercury is the nearest and the hottest planet. Venus is the brightest planet. It is also called the TWIN PLANET of the Earth.

26. SATURN AND URANUS SATURN IS A PLANET SURROUNDED BY THREE RINGS. URANUS, NEPTUNE AND PLUTO ARE THE OUTER PLANETS OF THE SOLAR SYSTEM.

27. MARS AND JUPITER Mars is the red planet. Jupiter is the largest planet that can accommodate thirteen earth’s simultaneously.

28. E A R TH

29. The Earth

30. Our Neighbour Satellite - MOON

31. Jupiter and its moons

32. S A TU R N

33. GALAXY A HUGE SYSTEM OF STARS IS CALLED GALAXY. OUR SOLAR SYSTEM BELONGS TO MILKYWAY GALAXY. THE STARS ARE SO CLOSE THAT THEY LOOK LIKE A WHITE GLOWING PATH . EG AKASH GANGA

34. METEROITES ARE SMALL PIECES OF ASTEROIDS WHICH COLLIDES AND BREAK INTO SMALLER PIECES,WHILE REVOLVING ROUND THE SUN.