Mercury

Mercury is the closest planet to the sun, and it is the smallest of the eight planets in our solar system. It is only 3,032 miles across, making it only a little wider than the United States! Much like Earth’s Moon, many craters dot Mercury’s surface due to the asteroids that frequently hit it.  

Mercury has a liquid iron core at its center that makes up over half the planet’s mass. The iron hardens as it cools, which has caused the surface to cave in, making the planet smaller. This sinking causes more cliffs and valleys to cover Mercury’s surface.  

Mercury travels around the sun very fast, with one year on Mercury taking only 88 Earth days. This speediness is what earned Mercury its name! It was named after the Roman god, Mercury, who was known for being fast. However, Mercury spins very slowly. One full rotation on Mercury takes 58 Earth days.  
 

_{These articles are written by library staff using library resources such as books, eBooks, and databases. Information can vary from book to book and database to database. Tickle Your Brain is meant to be a jumping off point for starting conversations about new topics of learning. It is not to be used as an authoritative resource.}