The solar system is made up of the Sun, the planets that orbit the Sun, their satellites, dwarf planets and many, many small objects, like asteroids and comets. All of these objects move and we can see these movements. We notice the Sun rises in the eastern sky in the morning and sets in the western sky in the evening. We observe different stars in the sky at different times of the year.

2. Have your own “TAKE-NOTE CHART”
THE EARTH
Diameter
Mass
Distance from the Sun
Days of Revolution
around the Sun
Hours of Complete
Rotation

3. Located far from the
centre of the galaxy
called the Milky Way is a
relatively insignificant
star which we call the
Sun. Surrounding it is a
collection of planets,
moons and other objects
which together form our
solar system.

4. The Sun is a large ball of very
hot gas, mostly hydrogen and
helium. It is the power house
of the Solar System. It's our
nearest star.
Scientists can tell what is
going on inside a star from its
color. Without the sun there
would be no life on Earth. We
depend on the sun for energy.

5. With a diameter of 1 392 530 km,
the Sun is a huge ball of gas. It has
333 000 times the mass of the
Earth and is composed of 92%
hydrogen, 7.8% helium and
less than 1% heavier elements.
It is the source of all the light,
heat and energy that is necessary
to create and sustain life on the
Earth.

6. THE SUN’S INTERIOR
Within the Sun there is a definite structure. At
the centre and extending out to about a quarter of
the Sun’s radius, is the core. Temperatures within the
core are approximately 15 million degrees celcius
and it is here that all the energy of the Sun is
created.

7. Diameter: 12 756 km
Mass: 6.57x10
Average distance from Sun:
149 597 900 km
Orbital period: 365.256 days (1 year)
Rotation period: 24 hr (1 day)
Number of known satellites:
1 (natural), 7000+ (artificial)
24

8. Earth is the third planet from the Sun and is
the largest of the small, rocky, terrestrial-type
planets. Of all the worlds in our solar system, it is
unique in that the composition of its atmosphere
and the presence of great oceans of water allow
life to exist and flourish on its surface.

9. HOW BIG IS THE EARTH?
The Earth is 12,742 km in diameter. It's the
largest terrestrial planet in the solar system. The
Earth weighs 5,973,000,000,000,000,000,000,000
kg. (That's nearly 6 trillion kilograms)
HOW OLD IS THE EARTH?
Scientific evidence
shows that the Earth is
4.6 billion years old.

10. Do you know that everyday and for one
year we are travelling the distance of 940 million
kilometers at the speed of 107,000 kilometers
per hour without leaving our homes and being
absent from work or school?
Planet Earth functions as spaceship that
brings us around the sun in the counterclockwise
direction (west to east). Such motion is called
revolution and one complete journey the sun
takes 365 ¼ days.

11. Perihelion is when the earth is closest to the
sun in its orbit around the sun. This takes place
on January 3rd. The earth is 147 million km.
away from the sun.
Aphelion is when earth is farthest from the
sun in its orbit around the sun. This takes place
on July 4, the earth is 152 million km. sway
from the sun.

12. WHAT IS ROTATION?
Rotation is the movement of
the earth around its axis once in
24 hours causing day and night.
(diurnal motion)
THE EFFECTS OF ROTATION ARE :
1. Parts of the Earth have day and parts of the
earth have night-results in the occurrence of day
and night.
2. It creates a centrifugal force which results in the
shape of the earth, being an oblate spheroid
(flattened at the poles and bulging at the
equator.)

13. The effects of revolution are:
1. The change of seasons
2. The varying lengths of day and night.
3. The changing altitude of the midday
sun at different times of the year

14. 1. The Earth spinning on its axis. Rotation
Revolution2. Going around a larger body. Rotation
Revolution
Revolution
4. Causes the Earth’s seasons. RevolutionRotation
5. Creates a year.
3. 24 hours. Rotation Revolution
RevolutionRotation
6. The moon going around Earth. RevolutionRotation

15. Diameter: 3476 km
Average distance from Earth: 384 402 km
Orbital period: 29 days 12 hr 44 min or
27 days 19 hr 18 min
Rotation period: 27 days 19 hr 18 min or 28 days

16. The Moon travels around the Earth in
an elliptical (oval shaped) orbit. Its
distance from the Earth varies from
356,000 km to 407,000 km.
Furthermore, having only one-
eightieth of the Earth’s mass, means that
the surface gravity of the Moon is just
one-sixth of the Earth’s. This means that a
60 kg person would weigh* just 10 kg on
the Moon.

17. The Moon has no atmosphere because
its gravity is too weak to hold on to any
gases it may originally have had. As a result,
temperatures vary considerably from –184
°C at night to 101 °C at noon. Since the
poles receive constant light and heat from
the Sun, they have a constant temperature
of –96 °C.

18. Earth
Revolution
Planet
Earth
ROTATION or REVOLUTION