What everything is made of
Ninety bricks, not a hundred and eighteen. There are a hundred and eighteen elements on the table, but around thirty are artificial and last milliseconds: the ones found in nature number in the nineties. And you do not even need them all. Ninety-eight per cent of the Earth's crust is eight, and almost all of the universe is two: hydrogen and helium.
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What is almost all of the universe made of?
- Hydrogen and helium
- All 118 in equal parts
- Oxygen and carbon
- Iron and nickel
Why The two lightest: nearly 98 % of the ordinary matter in the universe. Everything else —the carbon in your body, the iron in your blood, gold— was made inside stars and is, on a cosmic scale, the rounding error.