Smack in an asteroid to save planet Earth this week on planetary radio.

Welcome, I'm Matt Kaplan of the Planetary Society, with more of a human adventure across our solar system and beyond.

The Dart spacecraft will leave on a suicide mission in a couple of years.

It will slam into an asteroid called Didymos in the first

real test of how we might deflect a future object headed toward destruction of a major

city or worse.

Nancy Chabot is at the center of this planetary defense test.

She'll tell us all about it.

And why the study of small bodies like asteroids and comets is so fascinating.

Later we'll join Planetary Society Chief Scientist Bruce Betts for a look at our busy sky,

a look back in history, a more or less random space fact, and a new space trivia contest.

The Mars Science Laboratory Rover has entered a new region of the Red Planet,

senior editor Emily Loch Duvala is here with a preview.

Welcome back, Emily.

The news that you have for us from Curiosity is so fresh as we speak your blog post is not even

published yet, so fill us in.

Why is this a big deal?

Well, the big deal is that Curiosity just drove on to Clay.

And that may not sound like a very big deal,

but it is a very big deal to the mission. When the Mars community got together for years before they ever launched

curiosity, they selected a landing site where they figured they could find evidence for ancient habitable environments and curiosity has actually already done that

But the main piece of evidence or one of the most important pieces of evidence that led them to pick Gail Crater was the signal of a certain kind of clay that they could see from space.

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