Atom -

Our understanding of the atom has shifted from philosophical guesses to precise quantum models: What is an Atom?

: If you were to remove all the empty space from every person on Earth, the entire human population would fit inside the volume of a single apple. A Stardust Heritage Our understanding of the atom has shifted from

The atoms in your body weren't always yours; they have a cosmic history: : The simplest atoms, like hydrogen and helium,

: If an atom were expanded to the size of a professional sports stadium, the nucleus (where almost all the mass lives) would be no larger than a marble sitting on the 50-yard line. : The simplest atoms

: The simplest atoms, like hydrogen and helium, were created in the first few minutes after the universe began.

Perhaps the most mind-bending fact about atoms is that they are .