ACS: The Secret Science of Stuff - The Secret Science of ATOMS

Now you know that atoms are really small and that there are huge numbers of them, but here are a few other atom facts you might find interesting.

Where do atoms come from?

Believe it or not, the atoms on Earth, including the ones in you and everything around you, came from outer space. Some atoms came from the original Big Bang that created the universe, but most came from exploding and colliding stars.

Which atoms make up most of the stuff in the universe?

About 98% of the mass of the universe is made up of only two types of atoms: hydrogen and helium. That’s because these two elements make up stars like our sun and most of the stars in the universe.

What is an atom made of?

An atom is made up of parts that are way smaller than the atom itself. Here is an artist’s drawing of a model of an atom. The middle part of the atom is called the nucleus. It is made of tiny particles called protons and neutrons. Zooming around the nucleus are even tinier particles called electrons.  Most of the atom is empty space!


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Kindergarten, 1st Grade, 2nd Grade, 3rd Grade, 4th Grade, 5th Grade
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