Our Planet - The Earth (Our Habitat)
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| OUR EARTH |
Since ancient times man has been wondering about the wonders
of the sky. About the thousands of tiny twinkling objects as they appeared, and
those with the glowing tails moving at a very high speed.
Then arose the question why some of them shows motion while
some of them stick to their places? What holds them up their, so on and
many more questions to which they wanted an answer.
Today with the growth and advancement of science and
technology and the contribution of scientist and astrologers all round the
globe we are able to know a lot about our universe and its heavenly bodies of
which are so called earth is part of. These celestial bodies are the twinkling stars, planets sun
and innumerable of meteors, comets and asteroids. Of the three, only stars give of their own heat and light. Stars are hot bodies made up of very hot gases. They seem
very small in size because they are very far away from us. Sun too is a star
nearest to our earth than the other stars .This is the very cause that Sun
looks bigger.
One of the most common question is that are these stars countable?
In olden days when children used ask from their grandmother that how many stars
are there in the sky? She generally used to answer that there are as many stars
in the sky as the numbers of hairs on your head. However talking scientifically
astrologers also have not been able to count the numbers of stars in the
universe. Actually the extent of the universe is beyond our imagination so counting
them is prone to impossible, but we can see about six thousand of them from the
Earth.
SOLAR SYSTEM
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| SOLAR SYSTEM |
The word ‘solar’ comes from the Latin word sol, which means SUN.
Solar system means sun along with its eight planet and their thousands
of meteors, comets and asteroids etc with planets moving around the sun and
their satellites moving around the planets. Earlier there were nine planets but now there are only eight
with Pluto being excluded from the list of planets of our solar system as it was
very small and at far distant from the sun.
THE SUN
Sun is the largest member of the solar system being at its
center. All the planets revolve around the sun. The distance between the sun
and the eight planets varies. The average distance of the sun from the Earth is
about 150 million kilometers. The light
from the sun travelling at a speed of three lakh kilometer/sec
reaches the earth’s surface in
an about eight minutes and twenty
seconds.
The SUN
is the main source of heat and light on Earth supporting all forms of life on
Earth.
Its surface temperature has been
calculated at about 6000 degrees Celsius while the temperature is about 150
million degrees Celsius.
PLANETS
The heavenly bodies which do not
have their own heat and light and reflect the light of the SUN are called
Planets. The word planet means’ wanderer’.
They revolve around the SUN in their orbital path. They may either support life
like our Earth or may not support life like those of Jupiter (the largest planet
of our solar system ), The Saturn and so on.
Up till now Earth is the only known
planet by our scientists and astrologers where life exists. No other planets
inside and outside of our solar system have been detected with traces of life. Still
there is a big hope among the scientists and astrologers that there may be life
possible in some or the other planet, which may be far very far and very very
far away from us such that we have not been able to know or discover about them
in spite of the great effort put in by the scientists all round the globe.
In order of their distance from the
SUN planets can be arranged likewise:
(Table 1.1)
Planet
|
Diameter in
KM
|
Time for
One
Rotation
|
Time for
One
Revolution
|
Distance
from
Sun in KM
Minimum
|
Maximum
Distance from
Sun in km
|
Mercury
|
4,880
|
58,65 d
|
87.97 d
|
46.0 million
|
69.8 million
|
Venus
|
12,104
|
243 d
|
224.70 d
|
107.5 million
|
108.9 million
|
Earth
|
12,756
|
23.93 h
|
365.26 d
|
147.1 million
|
152.1 million
|
Mars
|
6,794
|
24.62 h
|
686.98 d
|
206.6 million
|
249.2 million
|
Jupiter
|
142,984
|
9.93 h
|
11.86 y
|
740.6 million
|
816.0 million
|
Saturn
|
120536
|
10.66 h
|
29.46 y
|
1.35 billion
|
1.51 billion
|
Uranus
|
51,118
|
17.24 h
|
84.01 y
|
2.75 billion
|
3.01 billion
|
Neptune
|
49,532
|
16.11 h
|
164.79 y
|
4.46 billion
|
4.54 billion
|
Pluto
|
2,274
|
6.39 d
|
247.68 y
|
4.45 billion
|
7.38 billion
|
Hence we see that, Mercury is
nearest to the SUN while Neptune is the farthest after Pluto (but now Pluto has
been excluded from the planet list of Solar System). This makes Mercury one of
the hottest planet and Neptune one of the coldest. Jupiter one of the largest
planet and Mercury is the smallest. Scientists and astrologers opine that
mercury due to the enormous heat and radiation of the SUN is becoming smaller
and smaller and a day will come when mercury will be vanished from our solar system.
Venus is the brightest of all and is popularly known as morning and evening star.
