I'm John Bachelor with Bob Zimmerman, who is my wheel critic, but not ordinary wheels.

Wheels on Mars.

Bob, you've been taking pictures of the Mars, Rovers, Wheels for several years.

What's the direction?

I'm not taking the pictures, John.

I have to clarify that.

I am actually grabbing pictures that the rover team periodically takes of the wheels of curiosity to see their

condition.

Because very early in the mission, they found those wheels were deteriorating faster than they

expected.

And so they take very careful care of those wheels, and they survey them periodically

to see how they're doing.

They have instituted software to try to protect the wheels across the rocky ground. Well, the most recent

pictures, I posted on behind the black earlier this week. The most recent pictures indicate

strongly that one wheel is getting very close to failure. That's not good sign. The rover has six wheels, so it could probably lose one, maybe two, maybe even three, depending on which wheels go.

But the fact is that one wheel looks increasingly close to failure.

And a second wheel is not in great shape as well.

This has been an ongoing issue.

They've done a good job of extending the life of these wheels,

considering the early damage.

Once they knew it was happening,

they've really stretched out things for a very long time.

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