This is CBS, I on the World.

I'm John Batchel with Behind the Black, Bob Zimmerman.

We're going to Mars, Curiosity.

I'm looking at the photograph in your site, Bob, and what I see is a very rough terrain for those wheels.

Where are they going?

Yes, this is interesting because what Curiosity has been doing for the last two of six weeks or so

is they, the scientists have apparently made a decision to abandon their original plan

route on Mars, on Mount Sharp on the slope in Gale Crater.

The original plan was to travel downhill, actually, to a mesa below them.

But that's really less interesting when you think about it than going uphill.

Because going uphill, they go to new geological layers they haven't seen before.

They go downhill.

They're just seeing the same layers they've explored previously.

And more important, there is a geological feature down the road uphill from them, they

call boxwork.

This is essentially, think about what boxwork is.

You see this in caves.

This is a series of irregular right-angled ridges across the surface of ground.

And it's quite large on Mars here, and it's an interesting geological feature.

They want to get to it.

So they made decisions instead of going on downhill, they would go up a canyon.

And they went up this canyon to the last six weeks and then cut over to a saddle to cross into a nearby western parallel canyon.

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