||Missions to Venus
Featured Mission: MESSENGER
NASA's MESSENGER mission will give us our first good look at Mercury in more than 25 years. What mysteries will it uncover?
Why does Mercury travel around our Sun faster than any of the other planets? Ask your science teacher if you need help.
Mercury- The Swiftest Planet
Mercury is the closest planet to our Sun. It is named for the ancient Roman god of trade and profit. Legend says Mercury's winged sandals gave him super speed. Mercury the planet is super fast, too. It zips around the Sun every 88 days - faster than any other planet. No wonder it got its name from the quickest of the ancient gods.
Mercury is the second smallest planet in our solar system. If Earth were a baseball, Mercury would be a golf ball.
WHAT'S IT LIKE ON MERCURY?
Imagine looking up at a Sun that is three times larger than what you see on Earth. That is how our Sun would look on Mercury. Because of Mercury's wild elliptical (egg-shaped) orbit and weird rotation, the morning Sun appears to rise briefly, set and rise again. The same thing happens in reverse at sunset.
Mercury is not has hot as you might think. Venus is actually hotter. The temperature on Mercury can change more than 1,000�F (530�C) between night and day. There is very little air - atmosphere - to hold in the heat when the Sun is not shining. The thin atmosphere also means meteors don't burn up, so Mercury is covered with craters. It looks a lot like our moon.
There is no water on Mercury. But there might be a little ice in deep craters. Mercury has cliffs and valleys just like Earth. Some cliffs are a mile high.
You would need very special spacesuit to visit Mercury. It would have to protect you from extreme heat and cold and dangerous radiation from the Sun. Even NASA's MESSENGER spacecraft, which launches for Mercury in 2004, needs a shade to protect it from the Sun's blistering heat and radiation.