Mercury is the closest planet to the sun and is smaller than Earth, making it the second smallest planet in our solar system. It is millions of miles from the sun and has an orange-red appearance. Mercury orbits the sun every 88 days and rotates at a speed of 48,000 kilometers per hour, which is one of its most unique characteristics. The document was written by a 7 and a half year old girl named Belle who enjoys science, math, reading, and pizza and corn with fish.