Index

Interstellar Clouds
Classes of Objects
Gas Giant Planets
Brown Dwarfs
Red Dwarfs
Sun-sized Stars
Large Stars
The Largest Stars
Impossible Stars
Star Clusters
Planetary Systems
Rocky Planets
Endless Cycle

Space Shuttle over Central Victoria - NASA Johnson Space Center Images

The dust and gas in the nebulae ejected by stars at the end of their lives forms new interstellar clouds. These second and later generation clouds are rich in heavy elements such as carbon, nitrogen, oxygen, silicon, sodium, calcium, aluminium and iron. The Solar System and the planets formed from such an enriched cloud. The heavier elements, concentrated closer to the Sun, and formed the inner, rocky planets.

The Earth, it minerals, its continents, oceans, atmosphere, the many living things that dwell there, the human population and everything they have made is built from these elements.