March 11, 2016 Auroras
Itasca County, Minnesota
Little did I know at the time (because I wasn't really expecting an aurora shoot), but this is the fifth anniversary of my first aurora shoot of Solar Cycle 24. This night was a bit less dramatic than the first one, but it was fun nonetheless. I had originally intended to come out to shoot the Zodiacal light after sunset, but other things had come up, and I wasn't as good getting my act together as I thought I would be, so I got a late start.
I drove north out of town and arrived at Long Lake, which is on the southern boundary of the Chippewa National Forest. There are no houses on the lake, the drive to the lake is not plowed during the winter, and there had been a few days of freezing and thawing, so the road was covered in deeply rutted, crusty, icy snow. I needed the high clearance of the Jeep to get to the landing, or I would have walked the half mile or so.
Given that the temperature had been close to 60 degrees earlier this week, the ice was getting softer, so I stepped carefully onto the lake. I took a couple pictures of the Zodiacal light, which had actually faded a bit because I was late to the show.
|The faint, remaining Zodiacal light extends upward from the horizon, just to the left of center.
However, I also looked north and saw that it was glowing a little bit. I pointed my camera that way and caught a very distant aurora.
|A weak auroral structure is visible at the northern horizon. My eyes could see just the glow but not the structure here.
This made me consider staying out a little longer to see if I could catch a brighter substorm right along the horizon. I was also intrigued by the foreground compositions that were possible along this lake. I walked north around the eastern shoreline and experimented with different compositions. When I got closer to the northern end, I checked the solar wind data with my smart phone, and I saw that some sort of abrupt change had occurred. The magnetic field had strengthened, and the vector was pointed more south, meaning the auroras would likely brighten a bit. Indeed they did.
|The auroras are getting brighter as the evening progresses, but solar wind conditions did not look that great until a sudden change occurred in the solar wind.
I continued to shoot near the northern end of the lake. I set my camera to start a long interval time lapse and set off to continue exploring the northern end of the lake. When I had had my fill, I started walking back to my camera but soon turned back and started to see some structure appearing. A substorm was imminent. I must get back to my camera and change the settings now! I repositioned to get more of the auroral arc.
|The auroras brighten further as the increasing magnetic field in the solar wind begins to impact Earth's magnetosphere .
As you can see, my lens was begining to fog up. I hadn't been planning on being out this long, so I hadn't brought handwarmers with me. Time to rush back to the car and remedy my fogging situation! It turns out that luck was in my favor because the substorm did not commence as I had anticipated.
I swapped lenses, replacing the Canon 24mm f1.4 with a Samyang 24mm f1.4. I also grabbed a hand warmer packet and put it in my pocket along with the Canon lens to warm it up and evaporate the fog. Shortly after I got out there, the substorm began. In a somewhat unusual evoluation, the structure soon faded, and the auroras went back to the pre-substorm oval form. I took this opportunity to go back north to where I had been when my lens fogged up.
|The anticipated auroral substorm now starts. It is 12:37 AM.
When I got to that spot, more bright structures began to move around on the horizon. I put my Canon lens, which was now fog-free again, back on my camera and shot a time lapse.
|After I move farther north, the substorm continues.
|The structures below are occasionally moving around quite quickly.
When this second round of excitement faded, I started back to the car because I wanted to get some sleep, and the first substorm of the night is usually the best. I continued to take a few shots along the way.
|Later on in the substorm, the auroras start to look a bit more diffuse but also cover a larger portion of the sky.
I took my last shot around 1:46 then packed up and headed home. The effects of being almost 50 years old must be getting to me, or else my body has finally learned, after decades of trying to force it, to fall asleep before midnight. I had a really tough time staying alert on my drive home. On earlier shoots, I would have this issue if I stayed up until dawn, but this week, it seemed to happen without staying up all that late. Who knows? Anyway, now that the clouds of an El Nino winter are mostly gone, I will be doing a bit more shooting again.
|My last shot at 1:46 AM.