Minnesota Now with Cathy Wurzer

Why northern lights have been more common in Minnesota this year

Northern lights glowing in the sky
Northern lights in Isanti at 10:20 p.m. on Aug. 11, taken with no filter and a three-second exposure.
Kari Vaughn

This year we’ve had ample opportunity to see northern lights, even in the Twin Cities. And if it feels like its been more than normal, you're not wrong. There likely will still be even more chances if you haven’t seen them yet.

We wanted to know why Minnesota has seen so many aurora displays. MPR News host Cathy Wurzer spoke with Bob Lysak, a professor at the School of Physics and Astronomy at the University of Minnesota.

Use the audio player above to listen to the full conversation.

Subscribe to the Minnesota Now podcast on Apple PodcastsSpotify or wherever you get your podcasts.

We attempt to make transcripts for Minnesota Now available the next business day after a broadcast. When ready they will appear here.

Audio transcript

INTERVIEWER: This year we've had ample opportunity to see Northern lights, even in the Twin Cities or close to the Twin Cities. And it feels-- well, it feels like it's been more than normal. And if you feel like that, you're not wrong. And there likely will still be even more chances if you haven't seen them yet.

We wanted to know why Minnesota has seen so many Aurora displays this year. So joining us right now to explain is Bob Lisak, a professor at the School of Physics and Astronomy at the University of Minnesota. Professor, welcome.

SUBJECT: Hi, Cathy.

INTERVIEWER: I'm one of the few who have not seen any of the auroras this season. It's kind of pathetic. How successful have you been?

SUBJECT: I haven't done very well myself. I haven't. I've been trying to see it from the city, which hasn't been very productive these days. I did actually see some from a plane going to Europe in May, but that's the best I got.

INTERVIEWER: OK, I don't feel so bad. And you're an actual expert. So many people probably don't know that the Aurora happens because of activity on the sun. Can you explain that?

SUBJECT: Yeah. Well, what happens during the sun has a magnetic cycle going through. It causes sunspots and flares. But the most important thing is it also ejects mass, what we call a coronal mass ejection, which is a big blob of plasma, which is ionized gas.

It's like a big, big shock that comes and hits-- if it hits the Earth's magnetosphere, it can disrupt the Earth's magnetic field. And that basically shakes particles loose that come into the polar regions, hit the atmosphere, excite the atoms and the atmosphere. And that's what makes the light.

INTERVIEWER: OK. Thanks for that explanation. Why have we been seeing then so many aurora borealis this year?

SUBJECT: Well, we're at-- the solar activity undergoes an 11 year cycle and we're not only very close to the peak of that cycle, but this particular solar cycle has been stronger than usual. It's something about 50% higher than the predicted values at this point. So there's been a lot more solar activity.

Of course, other factors that come into play is, of course, the sun will shoot out these blobs of plasma in all different directions. And of course, only when it hits the Earth does it affect us and causes aurora. So in a sense, there's a matter of luck where we've been in line to catch some of these CMEs, as we call them, coronal mass ejection, and they hit the Earth to make our auroras.

Another factor that comes in is that the weather has been pretty good. The atmospheric weather in the previous solar cycle of about 11 years ago, there was quite a bit of magnetic activity, but it seemed like it was a cloudy day every time. And of course, if it's cloudy, unless you get up in an airplane or something, you can't see the aurora.

INTERVIEWER: Sure. Wow. So we're not even at peak yet, though, right? I mean, I would think these would be relatively difficult to predict.

SUBJECT: Well, that's true. It is very difficult to predict. And the predicted peak is somewhere late in '25 or maybe '26. On the other hand, since it is somewhat unusual, I mean, we're well outperforming the prediction so far. So it's hard to tell what's actually going to happen.

We call it space weather, and it is quite a bit like the weather, is that you don't really know what's going to happen, certainly in the long term. Now, it takes about two or three days for these coronal mass ejections to hit the Earth if they're coming our way.

So when you hear them say tonight or tomorrow night might get an aurora, that's a pretty good indicator. But knowing what's going to happen a month or a year from now is virtually impossible at this point.

INTERVIEWER: Is this the most powerful sun cycle you've seen in your time?

SUBJECT: Actually, not. I was just looking this up. The peak that was around 1991 was a bit bigger than this one. And at that time, I remember that there were a lot of instances where I saw auroras just from the middle of Minneapolis and just walking out of the restaurant after dinner and you'd see the aurora. So it just seemed very, very common.

Now, of course, 30 years ago, the problem with city lights wasn't quite as bad as it is now. And of course, you had things like smoke from wildfires, and that makes it difficult as well. But that '91 or-- so '91, '92 solar cycle I think was the biggest in recent years.

INTERVIEWER: So it sounds like you and I still have a chance to see them, though, in the coming weeks and maybe month or so.

SUBJECT: Oh, absolutely There's going to be-- in fact, mostly, like I say, we're coming up to the peak or maybe even we're at it. But actually, more of the activity that causes aurora tends to take place in what we call the declining phase of the cycle when the sunspot number is going down. So I'd say people should be on the lookout for them for the next four or five years.

INTERVIEWER: All right. Well, I'm going to have my fingers crossed. That would be great to see them. Professor, Thank you for your time.

SUBJECT: All right. Thank you very much.

INTERVIEWER: Bob Lisak is a professor at the School of Physics and Astronomy at the U of M.

Download transcript (PDF)

Transcription services provided by 3Play Media.