it is very useful for student presentation and teacher teaching.

2. INTODUCTION
Satellites like moon, planets like earth asteroids,
comets, meteoroids, stars etc are called celestial
objects .
In this chapter we are going to learn about various
celestial objects.

3. THE MOON
 The moon is the natural satellite of the earth. Moon is the
closest celestial object to the earth. It takes 9.5 days for
moon to rotate the earth.
 The surface of the moon is covered with hard & loose dirt,
craters & mountains.
 Since there is no air & water, life is impossible on moon’s
surface.
 The first man to l& on moon was Neil Armstrong, followed
by Edwin larding & the last one Michael Collins of USA
 The were a crew of Apollo 11.
 The l&ed on July 1963

4. MOON’S SURFACE
 In 1969, the american astronaut, Neil Armstrong l&ed
on the moon for the first time, followed by Edwin
Aldin. They found the moon’s surface to be dusty &
barren. Craters, upto hundreds of kilometres wide,
cover its surface.
 It also has large number of mountain ranges, valleys &
lave plains. The moon does not posses any atmosphere
& water & thus, there is no weather. As there is no
atmosphere to trap heat, the temperature on the Moon
is extreme, ranging from 100°C at noon to -173°C at
night.

5. THIS IS THE MOON’S SURFACE

6. MOON’S LIGHT & PHASES OF
MOON
We are able to see the moon because the sunlight
falling on the moon reflected towards the earth.
The day on which the moon is not visible that day is
called new moon day. The day on which the moon is
visible is called full moon day. We have one new
moon day & one full moon day .
As moon revolves around the earth once every month
& moves around the sun along with earth, different
amounts of its faces are been seen everyday

7. This is the phases of the moon

8. THE STARS
 A star is a massive, luminous sphere of plasma held
together by its own gravity. The nearest star to earth is
the sun, which is the source of most of the planet’s
energy. Some other stars are visible from earth during
the night, appearing as a multitude of fixed luminous
points due to their immense distance.
 The pole star which appears stationary form the earth &
does not change its position its with time because it lies
on the axis of rotation.

9. CONSTELLATIONS
 The group of stars which appears to form some
recognizable shape or pattern is known as constellations.
Each constellation has been given a name signifying an
animal. A human being or some other object which it
appears to resemble.
 Some of the important constellations which we can see
during night sky are :-
a) Ursa major
b) Orion
c) Cassiopeia
d) Leo major

10. This is the constellations

11. URSA MAJOR
The ursa major constellation consists of seven bright
stars which are arranged is a pattern resembling some
what a big bear. The ursa major constellation is visible
during the summer season.
We can locate the position of pole star in the night sky
with the help of ursa major constellation. The ursa
major constellation appears to revolue around the pole
star in the night sky.

12. ORION
The orion constellation consists of seven or eight
bright starts.
The orion constellation is visible to us in the sky
during winter season.
The brightest star in the sky is called “sirius”

13. CASSIOPEIA
Cassiopeia constellation consists of 5 main starts.
The cassiopeia constellation is thought represent
queen seated on chair.
Cassiopeia constellation is visible during winter.

14. LEO MAJOR
 Leo major constellation usually consists of 9 main
stars.
 Leo means “lion”.
 Leo major constellation is visible during summer.

15. THE SOLAR SYSTEM
Our solar system consists of the sun & the eight
planets. The eight planets are Mercury, Venus, Earth,
Mars, Jupiter, Saturn, Uranus & Neptune. Besides
planets, the solar system consists of a large number of
minor planets or asteroids, a host of comets & meteors.
The gravitational pull (attraction ) between the sun &
these celestial bodies keep all of them revolving
around it.

16. SUN
It is located 93,000,000 miles from Earth.
the closest star to earth.
at least 4.5 billion years old.
Has a surface temperature of 10,000 degrees & a center
temperature of 27,000,000 degrees Fahrenheit.

17. SUN

18. MERCURY (BUDH)
Mercury is the planet which is nearest to the sun.
Mercury is the smallest planet of the solar system.
Mercury can be seen either as a morning star in the
eastern sky just before the sun rise or as an evening
star in the western sky just after the sun set.
Mercury shows phases like moon. No life exist on
planet mercury has no satellite.

19. MERCURY

20. VENUS (SHUKRA)
Venus is the closest plant to the earth. Venus is the
brightest object in the night sky. The hottest planet is
venus.
The planet venius can be seen either as a morning star
in the eastern sky just before sun-rise or as an evening
star in the western sky just after sun set.
Venus show phases like moon. Venus has no satellite.

21. VENUS

22. THE EARTH (PRITHVI)
Earth is the only planet in the solar system on which
life is known to exist.
Earth has one natural satellite called moon. & it has
1072 artificial satellites.
The earth takes 365 days & 6hrs to complete one
revolution & 24hrs to complete one rotation.

23. EARTH

24. MARS (MANGAL)
Mars is also called the red planet because its suface
appears to be red.
Of all the planets, mars is most like the earth.
The thin atmosphere of mars contains mainly carbon
dioxide with small amonts of nitrogen, oxygen, noble
gases & water vapour
Mars has two natural satellites.

25. MARS

26. JUPITER (BRIHASPATI)
Jupiter is the biggest planet of the solar system. It can
fit 133 earths inside it.
But when compared to the sun jupiter is much much
more smaller than the sun.
Jupiter appears to be a very bright object in the night
sky.
Jupiter is made mainly of hydrogen & helium.
Jupiter has 28 satellites.

27. JUPITER

28. SATURN (SHANI)
Saturn is the second biggest planet in solar system.
Saturn is also made up mainly hydrogen & helium.
The most disinguishing feature of saturn is the system
of colourful rings around it. The presence of well-
developed rings circling saturn makes the plant
unique in the solar system.
Saturn has 30 satellites.

29. SATURN

30. URANUS (ARUN)
Uranus was the planet to have been discovered with
the help of a telescope.
Uranus is the third biggest planet of the solar system.
The most remarkable feature of uranus is that it gas
highly titled axis of rotation. Uranus appears to roll on
its side while orbitting around the sun.
Uranus is made up of hydrogen & helium. The planet
has 21 satellites.

31. URANUS

32. NEPTUNE (VARUN)
The planet neptune is farthest from the sun & the
earth. Neptune is the second planet which was
discovered with the help of a telescope.
Neptune is the extremely cold planet. It is the 4th
largest planet of the solar system.
Neptune has 8 satellites.

33. Neptune

34. ASTEROIDS
There is a large gap in between the orbits of mars &
jupiter. This gap is occupied by a large number of
small objects that revolve around the Sun. These are
called asteroids.
Asteroids can only be seen through large telescopes.

35. COMETS
Comets are also members of our solar system. They
revolve around the Sun in highly elliptical orbits.
However their period of revolution round the Sun is
usually very long. A Comet appears generally as a
bright head with a long tail.
The length of the tail grows in size as it approaches the
sun. The tail of a comet is always directed away from
the sun.

36. METEORS
These are commonly known as shooting stars,
although they are not stars. They are called meteors.
A meteor is usually a small object that occasionally
enters the earth’s atmosphere.
At that time it has a very high speed. The friction due
to the atmosphere heats it up. It glows & evaporates
quickly. That is why the bright steak lasts for a very
short time.

37. METEORITES
Some meteors are large so that they can reach the
before they evaporate completely. The body reaches
the earth is called a meteorite.
Meteorites help scientists in investigating the nature
of the material from which solar system was formed.

38. ARTIFICIAL SATELLITES
The artificial satellites are man-made they are
launched from the Earth. They revolve around the
earth’s natural satellite.
Artificial satellites have many practical applications.
They are used for forecasting weather, transmitting
television & radio signals. They are also used for
telecommunication are remote sensing.

39. ARTIFICIAL SATELLITES BY
INDIA
India has built & launched several artifical satellites.
Aryabhatta was the first Indian satellite.
Some other Indian satellites are INSAT, IRS, Kalpana-1,
EDUSAT, ISRO etc.