We have eight planets in our solar system, each one circling the sun at a different distance. Earth is the third planet and we are in what is called the ‘Goldilocks Zone’. That means we aren’t too hot and we aren’t too cold; we are just right. This has allowed life to thrive on earth because the temperature is perfect enough to allow liquid water, which is believed to be one of the key elements to have life on a planet. You can’t tell the temperature of a planet by just looking at it, but you could make a guess at which one is the hottest.
Mars is reddish color and some people might have guessed that Mars is the hottest planet in the solar system. But just because it’s red, doesn’t make it the hottest. Mercury is the planet that is closest to the sun and therefore gets more direct heat, but even it isn’t the hottest. Venus is the second planet from the sun and has a temperature that is maintained at 462 degrees Celsius, no matter where you go on the planet. It is the hottest planet in the solar system.
So what makes Venus hotter than Mercury? Mercury doesn’t have any atmosphere, and atmosphere can hold and trap heat. Any heat that Mercury receives from the sun is quickly lost back into space. Venus is very close to the actual size of earth and viewing it has been difficult due to a very thick atmosphere of carbon dioxide. This thick atmosphere makes the surface of Venus hotter because the heat doesn’t escape back into space. The atmosphere on Venus is so powerful that the pressure would be ninety-two times more than what you would experience standing on a beach at sea level.
Venus has what is called a runaway greenhouse effect. It’s a never ending cycle of heat being trapped inside due to the rising carbon dioxide levels. This is what happens when an atmosphere absorbs too much carbon dioxide: the heat has nowhere to go. As the temperature rises it effects the entire planet, creeping deep into the depths of the core.
Many scientists around the world were skeptical as to a possible mission to Venus. Most thought that everything would burn up before the technology could send back any information. The Soviets sent a few missions to Venus, and the first few failed. Finally, in 1981, the Venera 13 mission made it through the hot layers of atmosphere and landed on the surface. It managed to keep from burning up for 127 minutes and sent color pictures back of the surface of Venus. Then, the transmissions stopped as the Venera 13 melted.
In 1990, NASA’s Magellan probe was able to reach Venus and ‘map’ what the surface was like with radar. Venus has a lot of plains, highlands and lowlands. Since Venus was named after a Greek goddess, many of the areas of Venus that were discovered also have female names, but some do not. After they named the Maxwell Mountains after James Clerk Maxwell, the Scottish physicist, it was agreed that from that point on, all new areas of Venus would have female names.
This missions to Venus have been great lessons in what happens when a planet has a high carbon dioxide level in the atmosphere and is being used today by scientists as they study our own planet in the concept of global warming and greenhouse gas effects.