The name Venus is derived from the Roman goddess of love and beauty, and is possibly so named because it was the brightest thing visible in the sky after the sun and the moon. It is also known as the morning star and evening star, because it looks so bright when observed from the earth. It is often visible by the naked eye.
Not much was known about this planet until just a decade ago, because Venus is covered by a very dense atmospheric layer, rendering observation next to impossible. Over the years scientists have devised new methods of observation, and have finally been able to unlock many secrets of our fascinating sister.
Venus is the closest planet to the Earth. It is known as our sister planet because it is so close to us, and because it is very similar in size and shape to the earth. It is a little smaller than the earth, and is more of a perfect sphere than the earth is. However, here's where the similarity ends. Venus has no satellites.
Venus exhibits a very curious spin. It spins in the direction opposite to all the other planets, including earth, with the result that in Venus, the sun rises in the east and sets in the west. In addition, it spins very slowly around its axis. The earth completes a spin around its axis in 24 hours, while Venus takes as long as 243 earth days to complete a spin around the axis. However, it moves around the sun at around the same speed as the earth does. While the earth takes 365 days to complete a round of the sun, Venus takes 225 days to complete a rotation around the sun. So, if you think about it, in Venus a year is shorter than a day!
The temperature of Venus is a searing 484 degrees Celsius on the side of the surface facing the sun - so high that it can melt lead! In fact it is so hot, that if you were really on the planet, you would see the ground glowing red. The high temperature is possibly due to the dense atmosphere surrounding it, which consists of almost 95% carbon dioxide, creating a runaway greenhouse effect. This is why Venus is much hotter than Mercury, even though it is twice as far from the sun.
What is a greenhouse effect?
The sun's solar energy penetrates the dense atmosphere to reach the surface, but when it tries to rebound off the surface into the atmosphere, these rebound wavelengths are absorbed by gasses like carbon dioxide on their way out. The heat is thus trapped on the planet, causing the temperature to soar. These gasses which absorb the rebound wavelengths are called greenhouse gasses. Venus's atmosphere largely consists of greenhouse gasses, which is why the planet is an environment disaster.
In addition to the dense atmosphere, Venus is also surrounded by a thick layer of clouds, composed mostly of sulphuric acid. These clouds circle the skies above Venus at a tremendous speed - about three times faster than hurricane winds! The pressure on the planet is also extremely high - almost a hundred times that of Earth.