Is there life among the clustered stars this week on planetary radio? Welcome to the travel show that takes you to the final frontier. I'm at

Kaplan of the Planetary Society. A million stars so close to each other that they

fill the sky. Is that where we should look for another civilization?

Maybe, says Roseanne D. Stefano. We'll ask her to explain.

You knew we'd talk about Planet 9 this week, right?

Emily Lockwala and Bill Nye will examine this brave new... this not always with him on what's up. We begin with the Planetary Society's senior

editor. Emily, tell us about Planet 9, if it's actually out there. Well, your

second phrase is the operative one. We don't know if it's actually out there.

We do have a new paper by Constantine Batigin and Mike Brown that explains a few oddities of the

Kuiper belt with a theorized ninth planet

lurking way out there in their distant reaches of the solar system.

And we hope to hear more about this direct from Mike Brown next week on planetary radio, but in the meantime this is causing

a lot of excitement.

Well, it is, of course, because it would be truly thrilling to discover a ninth planet.

And the nice thing about this paper is that if it's

there it makes some fairly strong predictions about where in the sky it should be.

Not that it would be easy to find, it's still a fairly faint object, likely not moving very fast at all,

because it's more than likely at the farther edges of its long elliptical orbit.

And it's located in a region of the sky that is pretty dense with stars.

So if it's there it's still not going to be easy to find, but at least now we know where

to look.

Can you in two or three sentences explain why Mike and Constantine decided that there was good evidence for this new world.

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