This is John Batchelor, conversation with my colleague Bob Zimmerman about the sun.

What I've learned from Bob over many years is that very little is known with any certainty

whatsoever about the sun, our star. Without it, we're not here.

So little is known that locating what is called the dynamo that contributes to the sunspot cycle and the 11-year high and low of the sun,

if that's what it is.

The dynamo is somewhere inside the sun, but where?

Bob goes through the possibilities and then comes up with data and research that points to one particular place.

It's reassuring that they're on the search.

Here's Bob to explain.

What drives the sun?

The dynamo.

It drives the sunspots.

Drives the cycle.

Drives the 11-year peaks and lows.

It's a joy not to know if you don't understand where they're going,

but at the same time, it's the sun.

More of this tonight.

So, you know, they don't really understand why the magnetic field flips its polarity in every 11 years.

They know that the dynamo and the magnetic field is what causes

that sunspots cycle of up and down number of sunspots, but they really don't understand

the dynamo itself. And to give you an idea how little they understand it, they don't even know

exactly where in the sun the dynamo is. There's theories that it would be near the surface.

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