Solar Storm's Impact On Earth Weaker Than Predicted
ROBERT SIEGEL, HOST:
We were bombarded from outer space this morning. A massive solar flare erupted from the sun Tuesday night, sending a correspondingly outsized solar storm our way. It slammed into Earth today at more than four million miles per hour. Before the storm hit, scientists, meteorologists, reporters all pondered possible communication disruptions, power outages, Peyton Manning would leave Indianapolis. Well, the result from this cosmic cataclysm, except for the Manning part, which really didn't have much to do with it? So far, not very much.
Joining me on the line is Joseph Kunches. He's a space weather scientist at the National Oceanic and Atmospheric Administration. First of all, all hyperbole aside, explain what a solar storm is, and what was it that hit the Earth at four million miles per hour this morning?
JOSEPH KUNCHES: Well, Robert, a solar storm actually is the culmination of what started on Tuesday night. There was an eruption at the sun, a solar flare, and it also included - part of the outer solar atmosphere was blown away, which we call a coronal mass ejection.
And, actually, that's really the interesting part to us. The solar flare piece doesn't do very much in terms of impacts, but the coronal mass ejection is this big cloud of charged particles and magnetic field that has a direction to it and it was exploded out of the corona and headed towards Earth and our forecasters here in Boulder picked it up. They were able to plot the path of the coronal mass ejection and they correctly predicted that it would go by the Earth and the Earth's magnetic field early this morning.
So the storm is sort of the culmination of everything that started at the sun and made its way to the Earth and now is affecting the Earth's magnetic field.
SIEGEL: Well, let's assume that we'd really taken it on the chin from a coronal mass ejection. What would happen? What impact would it have on our lives?
KUNCHES: Well, back during the last solar maximum, back in 2003 around Halloween, there were a series of events even stronger than the one that we're experiencing today. And they disturbed the Earth's magnetic field to the point where there were some interruptions in satellite operations. The airlines who need to communicate as they fly from North America to Asia over the pole rerouted their flights so they could ensure communications. Electric power grid operators felt unwanted induced currents in their systems and there were a number of other things that were technologically felt because the sun was so eruptive back then.
SIEGEL: In this case, none of that happened?
KUNCHES: In this case, some of that happened. Actually, the airlines took precautionary measures and they have rerouted some of their flights to ensure their communications. But the short answer, I think, is that this event didn't turn out to be as strong or as problematic as we thought maybe 24 hours ago.
SIEGEL: Why? Just - it was offline or it was weaker than you'd forecast?
KUNCHES: The best analogy I can give you is think of a pitcher throwing a baseball and you and I are going to be the batter for a minute and that's what the forecasters see as it comes off the sun. And we saw the pitch coming towards home plate and we were able to properly predict where it was going to pass and when it was going to get here, but there was one unknown as we couldn't see the spin on the ball. There's that important factor when it comes to the strength of magnetic storms after coronal mass ejection, which is the embedded magnetic field in the plasma cloud.
And, currently, we have no good way of knowing what that is until it's almost right on top of us, so that's what makes the predictions of the size of the storm so difficult.
SIEGEL: But can you now say that whatever impact there might be from the solar flare on Tuesday night it has happened already? This event is behind us?
KUNCHES: It's not entirely clear that it's behind us. We're still in the throes of it. We could get a surprise. The interplanetary magnetic field could flip back in the other direction, but chances are at this point, I think we've seen the worst that this one has to offer.
SIEGEL: And is it true that we get a good light show in the sky as a result of all this?
KUNCHES: That's the upside is that when the Earth's magnetic field is very disturbed, the Northern Lights brighten, as well as the Southern Lights and they move more equator-ward. But again, sitting here right now, these current conditions are such that I wouldn't expect over North America that the auroras would be very bright much south of the Canadian border.
SIEGEL: Well, Mr. Kunches, thank you very much for talking with us about it.
KUNCHES: You're most welcome.
SIEGEL: That's Joseph Kunches. He's a space weather scientist at the National Oceanic and Atmospheric Administration. He works in Boulder, Colorado.
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