Earth in the Solar System
Q39. What is a whitish broad band, like a white glowing path that
we see across the sky on a clear starry night?
is a cluster of millions of stars. This band is the Milky Way galaxy. Our solar
system is a part of this galaxy.
Q40. Write a short note on asteroids.
are numerous tiny bodies which also move around the sun. These bodies are called
asteroids. They are found between the orbits of Mars and Jupiter.
Q41. Name all the planets according to their distance from the
There are eight planets in our solar system. In order of their distance from
the sun, they are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
Q42. What is meant by the ‘Solar System’?
The sun, eight planets, satellites and some other celestial bodies known as
asteroids and meteoroids form the solar system. We often call it a
solar family, with the sun as its Head.
Q43. What are stars?
Some celestial bodies are very big and hot. They are made up of gases. They
have their own heat and light, which they emit in large amounts. These
celestial bodies are called stars. The sun is a star.
Q44. Why do we see only one side of the moon always?
The moon moves around the earth in about 27 days. It takes exactly the same
time to complete one spin. As a result, only one side of the moon is visible to
us on the earth.
Q45. How does a planet differ from a star?
Difference between a planet and a star
Some celestial bodies do not have their
own heat and light. They are lit by the light of the stars. Such bodies are
called planets. Example : Earth
Some celestial bodies are very big and
hot. They are made up of gases. They have their own heat and light, which
they emit in large amounts. These celestial bodies are called stars. Example
Q46. Why the Earth is called a unique planet?
Conditions favourable to support life are probably found only on the earth. The
earth is neither too hot nor too cold. It has water and air, which are very essential
for our survival. The air has life-supporting gases like oxygen. Because of
these reasons, the earth is a unique planet in the solar system.
Q47. Despite being our nearest star, the tremendous heat of the
sun is not felt so much. Why?
sun is the ultimate source of heat and light for the solar system. But that
tremendous heat is not felt so much by us because despite being our nearest
star, it is far away from us. The sun is about 150 million km away from the
Q48. Write a short note on Sun.
sun is in the centre of the solar system. It is huge and made up of extremely
hot gases. It provides the pulling force that binds the solar system. The sun
is the ultimate source of heat and light for the solar system.
Q49. How do meteoroids burn up?
these meteoroids come near the earth and tend to drop upon it. During this
process due to friction with the air they get heated up and burn. It causes a
flash of light. Sometimes, a meteor without being
completely burnt, falls on the earth and creates a hollow.
Q50. Write about Human-made Satellite?
Human-made Satellite is an artificial body. It is designed by scientists to
gather information about the universe or for communication. It is carried by a
rocket and placed in the orbit around the earth. Some of the Indian satellites
in space are INSAT, IRS, EDUSAT, etc.
Q51. Write in brief about all eight planets of solar system.
Mercury - One orbit around sun - 88 days
spin on axis - 59 days
One orbit around sun - 255 days
spin on axis - 243 days
One orbit around sun - 365 days
spin on axis - 1 day
of moons – 1
One orbit around sun - 687 days
spin on axis - 1 day
of moons – 02
One orbit around sun - 11 years, 11 months about 12 years
spin on axis - 9 hours, 56 minutes
of moons – 16
One orbit around sun - 29 years, 5 months
spin on axis - 10 hours 40 minutes
of moons - about 18
One orbit around sun - 84 years
spin around axis - 17 hours 14 minutes
of moons - about 17
One orbit around sun - 164 years
spin on axis-16 hours 7 minutes
of moons - 8