MadSci Network: Earth Sciences |
Jenna-lynne and Juliana, About 4-1/2 billion years ago, there was a big cloud of dust and hydrogen gas floating around inside our galaxy. After a while, gravity caused it collapse into a disk shape and spin faster, like a skater pulling in her arms. The gas also formed the Sun, and the planets Jupiter, Saturn, Uranis and Neptune, while the other planets, Mercury, Venus, Earth, Mars and pluto, are mostly made of dust (which formed rocks), with some gas. Now this dust is really made of elements (such as iron, nickel and aluminum), much heavier than the hydrogen, helium and other gasses that make up the larger planets. Actually, they were made by nuclear fusion inside red giant stars, long before our sun and planets existed. As a matter of fact, the material that makes up your bodies came from the earth, and therefore, the same stars! Have a great day, Keith Little