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Mercury Planet

Mercury Planet:

The planet closest to the sun and the smallest planet in the solar system. It is only about one-third the size of Earth. Mercury is a cratered ball of rock that looks much like our moon. Mercury has the greatest temperature range of any planet or moon in our solar system. The surface temperature on the daylight side of Mercury facing the Sun reaches 800 degrees Fahrenheit (427 degrees Celsius), a temperature hot enough to melt tin. On the night side facing away from the Sun, the temperature drops to -297 degrees Fahrenheit (-183 degrees Celsius). For comparison, the coldest natural temperature on Earth was -129 degrees Fahrenheit (-89 degrees Celsius) recorded in Antarctica. It takes about 88 days for Mercury to complete one orbit around the sun, at an average distance from the sun of about 36 million miles (58 million kilometers).