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| The planet Venus (Source: NASA) |
The temperature of Venus remains
same whether it is day
or night, equator or poles. Venus is called the sister planet of Earth but still there is huge difference in the environment of
these two planets.
The question arises why is
the temperature of Venus is so high?
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| The thick blanket of atmosphere around the planet Venus. (Source: NASA) |
The answer somewhere lies
in its thick blanket, its ‘atmosphere’. The atmosphere is very different from Earth. It is composed of
97% carbon dioxide, 2% Nitrogen and less than 1% of oxygen, water and methane.
There is also a substantial amount of sulphuric acid in the lower atmosphere
which forms clouds and causes rain of sulphuric acid. Thunders and lightning
also exist on Venus which is related to sulphuric acid clouds unlike water
clouds on Earth. The atmosphere is so thick that its pressure is 90
times the atmospheric pressure on Earth. This atmospheric pressure can press you as hard as
water 3000 feet beneath Earth’s Oceans.
Now after knowing about the atmospheric status of Venus, you will be thinking that how can atmosphere heat up Venus to such a high temperature? But you are missing 97% carbon dioxide and sulphuric acid, both are good Greenhouse Gases. So let us look at it more carefully. The Greenhouse Gases will allow the sunlight to enter into the atmosphere of Venus but will not allow them to go out into the space. In this process, heat start accumulating on the Venus and give rise to high temperature.
Now after knowing about the atmospheric status of Venus, you will be thinking that how can atmosphere heat up Venus to such a high temperature? But you are missing 97% carbon dioxide and sulphuric acid, both are good Greenhouse Gases. So let us look at it more carefully. The Greenhouse Gases will allow the sunlight to enter into the atmosphere of Venus but will not allow them to go out into the space. In this process, heat start accumulating on the Venus and give rise to high temperature.
The atmosphere of Venus has very
high reflectivity, that’s why it reflects most of light of sun and make Venus brightest object in sky. Due to its high reflectivity,
the surface of Venus is not visible to us. NASA’s Magellan mission to Venus during the early 1990s used radar to image 98 % of the
surface, and the Galileo spacecraft used infrared mapping to view mid-level
cloud structure as it passed by Venus in 1990 on its way to Jupiter. In spite of thick atmosphere, cyclones of high speed up
to 360 km/h exist on Venus, the reason of this is still not clear to scientist.
The surface Venus is also
much different than surface of Earth. Craters which are smaller than 1.5 to 2 Km do not exist
on Venus because small meteors burn up in the dense atmosphere
before reaching surface. It is believed that Venus was completely resurfaced by volcanic activity 300 to 500
million years ago. More than 1000 volcanoes larger than 20 Km in diameter are
still present on the surface.
We can see that the Venus is not
the place where any life form can survive. Still it is one of the amazing
planets of our solar
system.