Basic Building Blocks: HydrogenOur bodies are made of 70% water, which is essentially H2O, meaning we have twice as many atoms of hydrogen by percentage. The Big Bang happened 13. 8 billion years ago, and 379,000 years later, matter cooled and compacted to form hydrogen and heliumgases that all the stars we know are made of. Additionally, all the hydrogen that exists in this universe was created at that time. All the other atoms that make up the universe were either created by