Page 99 - SST Class 06
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One such famous group is the Saptarishi or Big is the main source of heat and light on the Earth.
Bear , which is a group of seven stars. This The average distance of the Sun is about 15 crore
constellation can be used to ascertain directions at km. The sunlight takes over 8 minutes to reach the
night. Its top two stars point to the Pole Star . The earth.
Pole Star is a bright star which always shines in The Sun is very hot. The temperature at its surface
the north direction. When we know one direction, is about 6,000°C, while it is about 1,50,00,000°C
it is easy to know the other three directions. at its centre.
F ind Outind Out The planets go round the Sun due to its
gravitational pull.
Find out the names of some more galaxies.
The Planets
THE SOLAR SYSTEM We have told you that there are eight planets. In
terms of size, the Jupiter is the largest. Other
The Solar System means the family of the Sun. The
planets in the decreasing order of size are : Saturn,
Sun is a star which is nearest to us. In fact, the Uranus, Neptune, Earth, Venus, Mars and
Earth goes round the Sun. The Earth is a planet. Mercury.
Like the Earth, there are seven more planets which
go round the Sun. In the order of increasing
Info Bits
distance from the Sun, these eight planets are Info Bits
Mercury, Venus, Earth, Mars, Jupiter, Saturn,
Until 2006, the Pluto was also considered to be a
Uranus and Neptune. All these planets go round planet, but now it has been downgraded in view of
the Sun. Their path is called the orbit .
its massive distance from the Sun.
Thus, the Sun with its all planets and satellites Four of these planets are made up of rocks and are
comprises the Solar System.
called terrestrial planets ; these are Mercury,
The Sun Venus, Earth and Mars. The other four planets are
made up of gases and are called gas giants . These
The Sun is a star. It is at the
centre of the Solar System. It are Jupiter, Saturn, Uranus and Neptune.
is the largest member of the The planets have no light of their own. They
Solar System. All planets in reflect the light of the sun. All planets are
this system go round it. The spherical in shape and revolve round the Sun from
diameter of the Sun is about west to east (except Venus and Uranus). The
109 times that of the Earth. It The Sun planets also rotate on their axes.
Uranus
Venus Mars
Mercury
Earth
Neptune
Saturn
Jupiter
Solar System
Exploring The Solar System
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