The planet Mercury was named by the Romans after their messenger god, Mercury. Mercury travels the fastest around the Sun, so it was fitting that they chose the god whose hat and shoes were winged, enabling him to move swiftly through the skies. The element known as Mercury was named after the planet.
Mercury is the closest planet to the Sun, located at a distance of 36 million miles away. It makes one orbit around the Sun every 88 days. Mercury is also the smallest planet, only somewhat larger than the Earth's moon. It is considered one of the terrestrial planets and has a rocky surface covered with craters. Unlike most other planets, Mercury is surrounded by neither moons nor rings.
Mercury's atmosphere is thin and primarily made of hydrogen, oxygen, helium, sodium and potassium. One day on Mercury lasts 59 Earth days, which is how long it takes for the planet to spin once on its axis. During the day, temperatures here can reach as high as 800 degrees Fahrenheit, or 430 degrees Celsius. Once the sun sets, the temperature can decrease to as low as -290 degrees Fahrenheit, or -180 degrees Celsius. As of May 2014, no life has been found on Mercury, and researchers doubt that living things could survive in its climate.