The northern lights have been popping off across the state this past week. The sun is at a peak in an 11-year cycle of solar activity — making it possible to see these shimmering green, pink and white light beams.
The cycle is expected to continue until next summer before petering out.
WCMU's Teresa Homsi spoke with Ryan Harriott with the Michigan Storm Chasers about forecasting aurora borealis and how best to spot the lights.
This transcript has been lightly edited for clarity and length. You can hear the conversation by clicking the LISTEN button above.
Teresa Homsi: With the aurora, can you first explain what they are, and why they happen?
Ryan Harriott: Aurora basically is a bunch of charged particles that leave the sun and collide with the Earth's magnetosphere (the planet's magnetic field), which can create these dazzling lights. It happens because of what we call coronal mass ejections or CMEs for short (expulsions of plasma and magnetic field from the sun).
Those occur when solar flares happen. Now, make a distinction here, not every solar flare is going to have a coronal mass ejection. Some solar flares do not. The Earth is basically a tiny speck compared to everything in the solar system, so to get a CME to hit us here on Earth, that leaves the sun, is a very longshot, so to speak.
So, we have to look at imagery, and then from there we can decide how fast it's moving, if it's going to have a chance of hitting us. Even then, it's not exact, and that's why it's so hard to catch the aurora because technology limits us on how much knowledge we actually have.
TH: There's been times where I've heard, there's a chance, so I go outside, and I see a slightly green, hazy, little cloud. You look through your phone, and it looks so much better, and I think, okay, that's it.
On Monday night, I stuck it out and actually saw the bright beams and all the colors and everything. And I never thought that I could actually physically see that. What's the difference between the green, hazy cloud and the actual light show?
RH: When you see the green overall arc, that is what you typically see up further north. If you go up to the U.P. or in Canada, for example, or Iceland or Alaska, you're going to see that is low-altitude aurora. But the higher up you go (altitude-wise), the darker the color becomes essentially.
Now, Monday, what you probably saw was a substorm. We can look at what we call magnetometers, which kind of measure the strength or the effects on the earth's magnetosphere in real time. So when we see these magnetometers dropping, so to speak, we know that there's energy building. Then we see a spike, we can know it's about to release.
It's like a burst of aurora, but those big pink, red, purple pillars you see are usually associated with those substorms.
TH: And how long do those typically last? Is there any type of pattern to the timing of it?
RH: They can vary. It's not the same every single night overall. They typically do happen in solar storms like Monday night. It's just a matter of when and how strong it's going to be.
As far as how long they last, they typically are very short-lived in terms of intensity and length. (I would say there's) about 5-30 minutes of active color. Some can last longer, it's just a lot (of factors) that go into it. But typically here, you're going to see them dance really vividly for 5-10 minutes, and they're going to start to fade.
TH: For someone like you who's been watching for them, for the last few years, does it ever get old to you?
RH: It doesn't. It's almost addicting. For a lot of my fellow chasers who I talk to, once you see it, you get hooked on it and you want to see more.
One time is just not enough. You want to keep on, keep on trying to catch it. It's sort of humbling, but it's also just like jawdropping in a way. And I think that kind of describes every aurora event that I've seen this year that burst into these big substorms.
You're trying to photograph it, but at the same time, you just want to stand back and go, wow.
TH: Do you run into a lot of people who have lived in Michigan most their lives and just never seen them?
RH: People message us all the time after these events, 'I've never seen it my life. Thank you. I've seen it the first time because of you.'
These people are everywhere, and we are in solar maximum, which is the peak of activity on the sun. So that's why we're getting all these chances at once. That's part of why we (Michigan Storm Chasers) exist, and we want to help people get there. But it's pretty common the further north you go, so we are blessed to live in a state where we have the chance to see it so often.
TH: Do you have any advice for people who would like to see the Aurora? What should they do?
RH: I would say that if you go aurora chasing, patience pays off. It's not going to be a walk outside and you're going to see it. You have to wait. You have to be patient. But if you expect the aurora every single time, every single night, exactly when these forecasts say you're, going be disappointed.
So it's very vital to practice patience when you're out there looking for it. It's going to take a little bit of time, but you'll get it eventually.
