If Earth had the same diameter as the head of a pushpin, how much would all of the other celestial bodies in the universe need to shrink to scale proportionally? It’s a fun, ridiculous question and ...

If you want to feel small and get a sense for the awesomely overwhelming scale of the universe and all of its planets and stars and empty space, watch this star size comparison video. It starts with ...

A neutron star is the densest object astronomers can observe directly, crushing half a million times Earth's mass into a sphere about 12 miles across, or similar in size to Manhattan Island, as shown ...