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Astronomy Cast, episode 238 from Monday, November 7, 2011, solar activity.

Welcome to Astronomy Cast, our weekly facts-based journey through the cosmos, where we help you understand not only what we know, but how we know what we know.

My name is Fraser Kane, I'm the publisher of Universe Today, and with me is Dr. Pamela Gay, a professor at Southern Illinois University, Everett's Film.

And Pamela, how are you doing?

I'm doing well, how are you doing Fraser?

Good, and once again, recording this is a live Google Plus Hangout.

Hello to all our Google Plus friends, they're all waving, you can't see it, joke never gets old.

Alright, so we don't have a lot of time for chitchat, you've got an airplane to catch, so we're just going to roll.

The sun looks like a harmless burning ball of fire in the sky, warm life giving and forever unchanging, but we know better, don't we?

It's really a massive ball of churning hydrogen plasma encased in twisting magnetic field lines, speckled with sunspots, and constantly discouraging vast plumes of radiation and charged particles.

Sun is very active indeed.

And you know what's cool Pamela, we are nearing the solar maximum.

Well, we're hoping that we're nearing the solar maximum.

Yeah, it's very weird this year, very weird, strange times we live in.

Yeah, yeah, so we're recording this in November of 2011, and they keep changing when they think our current solar cycle is going to peak, just because it's such a weird one.

It's behaving oddly, and so the Gaussian fits aren't working so well.

Yeah, currently looking at a maximum probably around May of 2013, which for an 11 year cycle is right around the corner.

Right. All right, so, so then, and I was getting ahead of myself and let's go back.

Come back. So the sun is a ball of plasma, hydrogen pulled together by its gravity in a nice state of equilibrium with the light pressure pushing out and the gravity pulling inward.

And that would seem to be this sort of state of perfect balance, but the sun is very active.

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