The document discusses the eight major planets in our solar system and other celestial bodies that orbit the sun. It provides an acronym to help remember the order of the planets from the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. The Solar System is estimated to have formed between 4.53 and 4.58 billion years ago and contains approximately 98% of the material in the form of the Sun, with the rest being asteroids, planets and other orbiting bodies.