earth is an interesting place where we live. We see high mountains, lush green
valleys, deep oceans, sea, river, ponds, as well as vast desert.
earth is one of the eight planets that revolve around the sun in the solar
system. Eight planets of the solar system are: Mercury, Venus, Earth, Mars,
Jupiter, Saturn, Uranus and Neptune. The largest planet in the solar system is
Jupiter, smallest planet is mercury, brightest planet is Venus and coldest
planet is Neptune.
is the fifth-largest planet in the solar system and the third-closest
planet to the sun. Earth is about 150 million km away from the sun. It is just
at right distance from the sun, have liquid water and layer of air to sustain
Is the earth really round?
The earth seems to be flat to us and it is
difficult to believe that earth is sphere with a bulge at its equator and
flattened at its top. Long back, people believed that earth was flat that’s
why they fear to sail far out to sea, as they may fell off the edge of the
earth! Then some sailor sailed around the earth and came back to the same place
from where they have started. Now it has been seen by astronauts from the space
that earth is round, flattened from the top and swelled at the equator.
Rotation of the earth
Spin a bangle on any table top. Do you see any
imaginary line in the spinning bangle? This imaginary line that we see is
The earth also spins on its axis. This movement is called
rotation. The earth spins from west to east and complete its one rotation
in approximately 24 hours. We don’t feel earth spinning because everything
including us is spinning along the earth at the same speed. It is the
earth's rotation that causes day and night.
Why do we have day and night?
is always moving on its axis which allows sunlight to shine on different parts
of the earth. The area of the earth facing the sun receives sunlight,
experiences day and the area of the earth which does not receive sunlight,
experiences night. At all time, half portion of the earth is lighted by the
sun and half of the earth remains in darkness.
Let’s understand this with an activity.
a globe and fix it on table. Now light a torch from front of the globe.
What do you observe?
can see that half portion of the globe is lit by the torch represents day and
the darker portion of the globe represents night.
How we can say that the
earth turns around like a top?
long stick in the ground in the sunlight. We can see the shadow on the ground.
Mark the shadow. Observe the shadow after of an hour. We can see that this time
size and direction of the shadow is different. Repeat this observation for next
2 to 3 hour. We will find that the size and direction of the shadow keeps on
changing every hour. Change in shadow position shows that the earth is
Revolution of the earth
the earth rotates, it also moves around the sun in a fixed path. This fixed
path in which earth moves around the sun is called Orbit. Movement of
the earth around the sun in its fixed orbit is called revolution. Earth takes
one year to complete one revolution. Earth is slightly tilted from its
axis. Earth tilt’s and its movement around the sun in its fixed path causes