Everyone knows that the universe is huge, but no one could have imagined how staggeringly immense the universe, or multiple universes, may actually be.

What could be more startling than many universes - multiple universes, innumerable universes, perhaps an infinite number of universes? But does the multiverse really exist?

Do stars and spaces go on forever? Do the numbers of galaxies, and even of universes, have no end? Here's how infinity enriches appreciation of reality.

They warp space and time, squeeze matter to a vanishing point, and trap light so that it cannot escape. How can black holes perform such stupendous tricks, and what can we learn from them?

Here's the claim: cosmic conditions that allow complex structures - galaxies, stars, planets, people - depend on a few "constants of nature" lying within tight ranges of values. But is fine-tuning valid?

When we speak about the future of the universe, we mean when the sun burns out, when galaxies collide, when everything flies apart and ultimately evaporates. Do the untold billions and trillions of years from now make it irrelevant for us today? No. The far, far future of the universe conveys meaning now.

In the far, far future, what happens to planets, stars, galaxies, black holes? What's the 'Big Rip' and the 'Big Crunch'? And if 'multiple universes' exist, if one universe ends, do others begin?