Smashing holes in Mars in Mars this week on planetary Radio. Radio. Welcome to the Travel Show that takes you to the Final Frontier.

I'm Matt Kaplan of the Planetary Society.

Chris Carberry heads an organization called

Explore Mars.

He'll tell us how he hopes to drive small penetrators deep into the red planet's surface

to look for life, not past life, life that's active right now.

Emily Lachwaala will show us where a tiny lander will touch down on a comet, while

Bill Nye says NASA is about to decide who will launch astronauts toward the

International Space Station and then there's our weekly visit with Bruce Betts for

what's up. We begin with the Planetary Society's senior editor.

Emily, we could talk about Hayabusa too.

Maybe we'll mention that again at the end.

But I'm really fascinated by this piece that you These are beautiful images, some of which you assembled here.

People don't be afraid to zoom in on these because you can get right in close on them

and they show off these ellipses, these five ellipses on this comet.

What goes into deciding where to put a lander on a comet?

Well, mostly it's where can they get the lander on the comet?

Because this little lander that they have,

it's not guided on the way down.

So once they let it go, it's going to drop wherever it's going to drop.

And so they have to understand the gravitational field around this strange lumpy object,

and they have to find a location that the little lander will be able to settle down on without sliding down too steep a slope

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