This document summarizes the key facts about the planets in our solar system. It discusses the 8 major planets - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune - as well as Pluto. For each planet, it provides details on its size, distance from the sun, composition, and other distinguishing features. The summary concludes that the solar system formed 4.6 billion years ago and currently contains 9 recognized planets.