You probably know your neighborhood well. You know where your school is. You know how to get to the park. You know some nearby stores.
But how well do you know Earth’s neighborhood? You can think of Earth’s neighbors as all the objects in our solar system. These objects include planets. A planet is a large object that moves around a star.
There are eight planets in our solar system. Scientists put these planets into groups. The four planets closest to the sun make up one group.
The Earth
Planets Closest to Our Sun
The four planets closest to the sun are Mercury, Venus, Earth, and Mars. These planets have a lot in common. They are mostly made up of rock and metal, so they all have hard, uneven surfaces.
Because of their content, the planets closest to the sun have high densities. This means that these planets are made up of condensed, or tightly packed, materials. They also share the qualities of having slow rotation and solid surfaces.
The rocky planets closest to the sun are also alike in other ways. They are small compared to most of the other planets in our solar system. These planets also do not have many moons, or objects that rotate, or move, around a planet.
The rocky surface of Mars