The planet Mercury is the closest planet to the Sun and is also the smallest planet in our solar system. It's atmosphere is very thin so temperatures on the planet Mercury is incredibly hot in the day and extremely cold at night.
Closest to the Sun...
Planet Mercury has a short temper!
With little atmosphere to defend Mercury from meteorite and asteroid impacts, the surface of the planet is covered in craters and looks very similar to our Moon. It's also about the same size!
Mercury was named after the swift messenger of the gods from ancient Roman mythology, because of it's very fast orbit around the Sun.
Here are some additional facts about Mercury:
*One year on Mercury is approximately 88 Earth days. That's how fast the planet orbits the entire Sun!
*The planet can reach temperatures over 800 degrees in the day and drop to -300 below zero at night!
*Mercury can only be viewed in the morning or twilight.
*Only about 85% of Mercury has been mapped out by spacecrafts. In 2011 the MESSENGER spacecraft will start its orbit and will begin mapping out the remainder of the planet.
Return to the kids Solar System page!