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Physics.org: A Grain of Sand Covers 10,000 Galaxies
A fascinating look at how big our solar system really is. Shows how we can only see a tiny bit of our vast universe.
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Atoms in Motion: All Matter Is Made of Atoms
Atoms are very, very small. Atoms are so small that it is often said that there are as many atoms in a single grain of sand as there are grains of sand on all of the world's beaches - certainly a difficult thing to prove, but you get the...