The document describes the planets in our solar system. It begins with Mercury, the smallest planet closest to the sun, and ends with Neptune, the farthest planet from the sun. In between are descriptions of Venus, Earth, Mars, Jupiter, Saturn, Uranus, and the moon. The solar system consists of the sun and eight planets that orbit it in a counter-clockwise direction. It is estimated to have formed between 4.53 and 4.58 billion years ago, with the sun containing around 98% of the material in the solar system.