Probably most galaxies are truncated—the density of stars in the disk drops off sharply. But NGC 300 just seems to go on forever. The density of stars in the disk falls off very smoothly and gradually.

There’s as many atoms in a single molecule of your DNA as there are stars in the typical galaxy. We are, each of us, a little universe.

You should boot from a clean disk before removing a virus. Some viruses can't be cleaned any other way.

Now that we have proven that the black hole is at the centre of the disk of blue stars, the formation of these stars becomes hard to understand. Gas that might form stars must spin around the black hole so quickly - and so much more quickly near the black hole than farther out - that star formation looks almost impossible. But the stars are there.

There could be shadow galaxies, shadow stars, and even shadow people.

There are at least as many galaxies in our observable universe as there are stars in our galaxy.