We got lucky. When it happened we were well positioned to view, and photograph the show.
With favorable conditions forecast I had been watching the sky for over a week. The fickle southeast Alaska weather had provided any number of beautiful clear nights, our even more fickle Sun was producing conditions favorable for geomagnetic activity. The two conditions finally produced a nice auroral show.
Even better, that night we were moored to a state float rather than simply sitting at anchor, or even worse, docked in a town or city. In Helm Bay, 22 miles north of Ketchikan, we had a beautiful dark sky and a perfect setting to watch the show.
With a float I had a stable platform from which to shoot time lapse video, no rocking or swinging at anchor. I could set up the camera and tripod and let the intervalometer click away for over an hour.
The video is made from 360 separate exposures compiled into a video about 30 seconds long. Each frame was 10 seconds at ISO6400 using a Canon 6D camera and a Rokinon 14mm f/2.8 lens set to f/3.2. The frames are projected at 12 frames per second in the version below.
The ten second frames are still too long, the glowing bands of light move quite quickly, at times rippling across the sky. The result is that the patterns and motion in the aurora is blurred.
The aurora was quite bright, my usual 15 second night sky shots actually overexposing. I dialed back the exposure a bit, and should probably have dialed it back a bit more.
The island is home to a vibrant community of photographers, a mix of professionals and serious amateurs. There is one set of photos everyone, and I do mean everyone wants… Dual lasers on the Milky Way.
Just occasionally both of the keck telescopes, and both lasers, are focused on the center of the galaxy, both stabbing right at the heart of the Milky Way.
Opportunities to see and photograph this are few, and occur strictly during the summer months of June to August, when the Milky Way is high overhead. furthermore, these opportunities occur only when Andre Ghez and her UCLA Galactic Center Group have both telescopes scheduled.
July 25th was such a night, a good opportunity to get both lasers. Andrea’s group has the first half of the night, turning over the ‘scopes to other astronomers just after midnight. Actually there were a few nights this particular week, we just chose the 25th. After this galactic center season is over, at least until next year.
Another night on the summit for photography, another night of dual lasers working the sky above the Keck telescopes.
I have never really had a chance to properly use the old Celestron mount for photography after finishing it a few months back. Short tests, but nothing properly following the sky for hours on end as the equipment was meant to do.
It works, and it works very well indeed.
The video below contains 2.5 hours of time-lapse at 15 second for each exposure for 557 frames. Put that together and render at 24fps and you have the following result…