Transcripts

Cosmologist and astrophysicist Janna Levin, author of the book How the Universe Got it's Spots, says the universe appears to be finite, sort of.

Well it's finite in the most elegant way imaginable and that is that there is no boundary and no edge and that's what's so difficult to imagine. A simple example would be the surface of the earth. People used to fear that if you went exploring off of the coast of Spain, you would eventually fall off of the edge, but we know now there's no ugly edge. That's the kind of thing we're imagining for a three-dimensional universe - only it's very difficult to visualize but it does have that elegance in the sense that if I left the earth in a rocket and I traveled in a straight line, I would eventually come back to the earth again. There is no boundary, no edge, and therefore no meaning to the question "What's on the other side?"

And Janna says, scientifically speaking, it is likely that there are other planets like our own.

It's recently become much more important astronomically because we're at the point where we might actually be able to observe such planets. They're very hard to see because planets aren't intrinsically luminous, but what we can look for are stars that have similar properties to the sun and that we think might have a planetary system around them. It's a really viable and important program in astronomy right now.

At somethingyoushouldknow.net, I'm Mike Carruthers and that's Something You Should Know.