Does the Universe Have an Edge?

For all intensive purposes, the Universe has no edge. CREDIT: European Southern Observatory View full size image

No. That's the simple answer. And I recommend you stop there and be satisfied, because as soon as you dig deeper, you'll be as confused as the average cosmologist.

One wild cosmological idea imagines the universe as a soccer ball with segments and seams. Think of each segment as a magical sheet of paper. If you traveled to any side, you'd reappear where you started. Toss in a little pixie dust and a few elves, and this one starts to make sense!

You're still reading. Okay, here goes: Imagine ants crawling on a balloon. They can crawl forever and never reach an edge; at best, they might return to where they started.

Of course now you're thinking, "Hey, if I'm inside the balloon and I head outward, I will hit it and that'll sure seem like an edge." Thing is, the balloon is expanding so rapidly that you'll never get there. And even if you did, those same wacky cosmologists that dreamed up the ants-on-a-balloon explanation say they have no clue whether there is more of our universe (or more universes) beyond the limits of the observable one.

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