Photobombed by Aurora

If you’re interested in Astrophotography, you probably know how difficult it is to get a “good” night under the stars. Conditions need to align if you want to come away with a final image worth sharing. Here’s the scorecard to success:

Sunset/sunrise time. Summer months in Canada aren’t very dark for very long.
Seeing and transparency. Living near the Rockies means I take what I can get.
Overnight temperature above -10 Celsius or the gear complains.
Little to no moon glow. 30% moon or lower gets me excited.
No clouds, obviously!
Wind below 25km/h.

When a night checks most of these checkboxes, you need to seize it. During the summer months, I travel to dark sky locations outside the city and spend the night. We’ve battled significant forest fires during the month of May, which produce thick smoke that can hang around for weeks at a time. Earlier in the week, the smoke was the thickest I’d ever seen.

To my surprise, the winds shifted and I had the opportunity to drive out and attempt some astrophotography. I just hoped the forecast would hold the smoke and clouds at bay. Turns out, that would be the least of my problems!

As evening turned to dusk and I waited for darkness, I glanced around the horizon. Thick banks of smoke surrounded my site, but I was intending to shoot a target high enough in the sky to avoid hazy images. One cloud bank in the North began to look a bit odd — it was glowing!

It goes without saying, energized particles in Earth’s atmosphere glowing red, green, and purple don’t play nicely with deep-sky astrophotography. But, I was happy to pause and enjoy the show.

As the lights faded, I programmed a batch of instructions for my telescope and retreated to my tent for the night. Rather, for about an hour. I awoke to the sides of my tent flapping around like someone had told a gang of toddlers there was candy inside. The winds had picked up and my telescope was hanging on for dear life.

On a normal night, my imaging mount tracks a guide star at ~0.4 arc seconds per pixel. It needs to hold the camera sensor really steady in order for the stars to be perfectly round, pin-pricks of light. The guide graph was reporting spikes of motion reaching 90 arc seconds per pixel. This is a nightmare scenario.

What a normal night of guiding looks like. Kind of like an ECG.

This night’s graph. It would make an interesting plot line for any TV medical drama!

With a couple hours left before sunrise, I moved the whole apparatus behind my vehicle. Did it help? Not really. I think the wind subsided around 3am, so that’s neat.

Once home, I reviewed the individual exposures which are each 250 seconds long. These will be stacked together to make my final image. I wasn’t surprised that lots of them looked like some type of modern art. The stars were smeared, circles had become lines, or each star had an evil twin. Abstract isn’t what we’re going for here, so those frames were tossed.

Here’s a bad frame. What a waste of 250 seconds!

All said and done, my final integration was 2 hours, and 30 minutes in total. I’d certainly hoped for more time, but that’s part of the chase — I’ll get more next time!

Have you met Fred?

No Sleep for You

Dan of the North