Some facts about the solar system to teach children in elementary school are that it is found in the Milky Way galaxy, is approximately 4.6 billion years old and consists of the sun and different celestial objects, such as planets, moons, asteroids and comets. Although the solar system originally was made up of nine planets, now scientists consider that there are only eight planets. In 2006, the planet Pluto was demoted to dwarf planet status.
Eight planets orbit the sun, which is a massive star that has a powerful gravitational force. The asteroid belt, Kuiper belt and Oort Cloud also are in the solar system, and they consist of a large number of celestial objects.
There are four inner and four outer planets. The inner planets are Earth, Mars, Venus and Mercury. The outer planets are Jupiter, Neptune, Uranus and Saturn. With the exception of Mercury, all the other planets have moons, which orbit about them. In the solar system, the smallest planet is Mercury, and the largest is Jupiter.
Earth has one moon or natural satellite while Jupiter has the most with 63 confirmed moons. Some interesting facts about these moons are that many have names related to Greek mythology, such as Leda, Calisto and Ganymede, These are moons of Jupiter. Ganymede is Jupiter's largest moon.
The outer planets have certain unique characteristics. Jupiter has a great red spot, which is an enormous storm that has existed for more than 300 years. Jupiter, Saturn, Neptune and Uranus are called gas giants because they consist of gases, including helium and hydrogen.