1. Our solar system began as a cloud of dust and gas.
2. An exploding star, called a supernova, disturbed the cloud.
3. The explosion made waves that squeezed the cloud.
4. The cloud began to collapse.
5. A powerful force called gravity pulled the gas and dust together.
6. The solar nebula began spinning.
7. The disk grew thinner as the solar nebula continued spinning.
8. The solar nebula became hot and dense in the center. The surrounding disk of gas and dust that was cooler at the edges.
9. The center got so hot it became a star we call the Sun.
10. Near the center only rocky material could stand the heat.
11. Icy matter and rock settled on the outside of the disk where it was cooler. Planets such as Jupiter formed from this.
12. Some groups of particles grew bigger and bigger. These later became planets and moons.
13. The particles of dust and gas began to stick together.
14. This turned the cloud into what is called a nebula.
15. Wind blew gas and dust around the solar system. This leftover gas and dust is now called meteorites.
Parent Tip: Review the logic above to help your child master the concept of formation of the solar system worksheet.
