2. Earth’s Physical Characteristics
Earth is one of the terrestrial planets
in the solar system. Among others are
Mercury, Venus, and Mars.
Terrestrial planet is a planet that is
composed primarily of silicate rocks
or metals.
3. Earth’s Physical Characteristics
The terms are derived from Latin
words (Terra and Tellus), so these
planets are, in a certain way, “Earth-
like.”
Only on terrestrial planet, Earth, is
known to have an active hydrosphere.
4. Facts about Earth
Average distance from the sun
Equatorial diameter
Circumference around the
equator
Surface Area
Rotational period
Revolution period around the
sun
150 000 000 km
12 756.32 km
40 075.16 km
Land area: 148 300 000
Water area: 361 800 000
23 hours, 56 minutes, 4.09
seconds
365 days, 6 h, 9 min, 9.54 s
5. In 500 BC, Pythagoras, a Greek
philosopher, recognized that Earth
has a curved shadow on the moon.
200 BC, Eratosthenes, a Greek
astronomer, was the first to compute
Earth’s circumference and tilt.
Earth’s Physical Characteristics
6. Isaac Newton predicted nearly three
centuries ago that Earth is more
nearly round than any other shape.
Gravity contributes to Earth’s oblate
spheroid shape.
Lithosphere is the topmost solid part
of Earth. Earth’s crust forms the
upper part of the lithosphere.
Earth’s Physical Characteristics
7. There are four major landmasses on
Earth. Each major landmass is made
up of one or more continents.
Continent - is a large land area that
measures millions of square kilometers
and rise high above sea level.
Earth’s Physical Characteristics
8. About 70% of earth’s surface is covered
by water. This is called hydrosphere.
The hydrosphere includes Earth’s oceans,
rivers, streams, ponds, glaciers, lakes and
other bodies of water.
Earth’s Physical Characteristics
9. Earth’s Motion
Day and Night
Earth is the third planet from the
sun. It revolves around the sun
following an elliptical orbit.
It also rotates on its axis as it travels
around the sun.
Earth rotates on its axis every 23 hours
and 56 minutes, which makes one day.
10. Earth’s Motion
Day and Night
As Earth rotates, part of it faces
the sun while the rest of the Earth is in
darkness.
As Earth continues to rotate, the part
experiencing daytime will soon
experience nighttime and the part that
as in darkness will soon be facing the
sun.
The position of the sun is fixed and
11. The sun rises in the east and sets in the
west because Earth rotates from west
to east.
The length of the day is measured
from the time the sun rises to the time
the sun sets.
Earth’s Motion
12. The amount of sunlight received by
Earth varies with the tilt of the axis.
The distribution of solar radiation
caries among the three regions of
Earth. (the equator, the Tropic of
Cancer, and the Tropic of Capricorn.
Earth’s Motion
13. The equator is an imaginary band that
encircles the Earth;
the Tropic of Cancer is located
23.5°north of the equator,
and the Tropic of Capricorn is
23.5°south of the equator.
Earth’s Motion
14. Causes of Season
While Earth is rotating, it is also
revolving around the sun.
Earth’s revolution around the sun,
which takes 365 ¼ days to complete,
is the basis for our measurement of the
year and season changes.
15. Causes of Season
The cycle of seasons is caused by
Earth’s tilt towards the sun.
These seasons include summer, winter,
autumn, and spring.
Because of the tilt of Earth’s axis, the
length of day and night changes.
16. Causes of Season
On June 20 or 21 every year, the North
Pole experiences summer solstice.
The northern hemisphere experiences
its longest days at this time, while the
southern hemisphere experiences
shortest day.
17. Causes of Season
After June 21 of every year, the sun
seems to move lower and lower in the
sky until December 21 or 22 of that
same year when the winter solstice
occurs.
18. Causes of Season
Twice a year, neither the north pole
nor the south pole is tilted towards the
sun; this occurs in spring and autumn.
During these times, days and nights
are of equal length all over the world,
known as equinoxes.
The word equinox means “equal
night”.
19. Causes of Season
In Northern hemisphere, spring begins
on the vernal or spring equinox, which
generally falls on March 20 or 21 of
every year.
Autumn begins on the autumnal
equinox, which falls on September 21
to 22 of every year.
20. ECLIPSES
As the moon revolves around the
Earth, and Earth and moon revolve
around the sun, they block out some of
the sun’s light, producing shadows.
Sometimes, the moon moves into
Earth’s shadow or may cast a shadow
onto Earth.
21. ECLIPSES
A lunar eclipse or eclipse of the moon
occurs when Earth passes between the
moon and the sun and its shadow
obscures the moon.
22.
23. ECLIPSES
A solar eclipse occurs when the moon
passes between Earth and the sun and
its shadow falls on Earth.
24. ECLIPSES
A total eclipse of the sun or the moon
occurs when either of the two bodies
becomes completely obscured.
Moon frequently passes through the
outer area of Earth’s shadow. This
causes a partial eclipse in which the
moon’s reflected light is dimmed.
25. ECLIPSES
The moon exerts a pull on Earth, and
results in the rise and fall of ocean
water levels as the moon moves in its
orbit around the Earth.
The rising and the falling of the water
level that occur during the day are
called tides.
Tides are caused by moon’s
gravitational pool.
26. ECLIPSES
The rise in water level due to the pull
of the moon is called high tide, which
usually happens every 12 hours.
Low tide occurs when water falls to its
lowest level.
The change from high tide to low tide
is caused by the rotation of Earth and
the effect of the moon’s gravity.
27. ECLIPSES
During the moon and full moon, the
lunar and solar tides together produce
the larger spring tides.
At the first and last quarters of the
moon, lunar and solar tides produce
the smaller tides called neap tides.
