This is CBS Eye on the World.

Here's John Batchler.

I am Mars, two mysteries I learned from the proceedings of the National Academy of Sciences

PNAS by Dr. Ken Croswell, the distinguished astronomer of Lives of Stars.

This is about a mystery of planets and how they acquire moons.

The two moons of Mars, Phobos and Demos.

Ken a very good evening to you.

Phobos and Demos, what do they look like, Ken?

How big are they?

And what is the mystery?

Good evening to you.

Well, good evening, John.

Yes, they have been much neglected over the years.

The missions to Mars, almost all of them have concentrated on Mars and not on its moons.

Now, that's not simply because we've ignored them totally.

It turns out there were some spacecraft from what was once the Soviet Union and later

Russia, but those missions to the moons of Mars failed.

Anyway, you asked me, what are these moons like?

What size are they?

How big are they?

All that stuff.

Anyway, they're very small.

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