One of the things I love about photography in general, and astrophotography in particular, is you never quite know what you’ll get.
Take, for example, Tim Ashby-Peckham, who saw that the International Space Station was going to make a nice pass of his location in the early evening of Nov. 1, 2015. He set up his Canon 70D camera on a tripod, aimed it in the right direction, and waited. Once the ISS came into view, he started snapping away.
Take a look at the photo above. You can see the ISS as a long streak, since it moves a lot during the 30-second exposure. But take a closer look. See the wiggle in the streak at the bottom?
Here, let me enlarge it (I’ve rotated the shot to make it easier to see, and inset a zoom on the piece in question):
Ah, see it now? Clearly, something whacked his tripod during the shot. Again, I’ve ruined many a fantastic photo doing exactly that with my foot (as has pretty much every photographer ever); it’s easy to do when it’s dark out.
But the wiggle doesn’t look like the usual foot-in-tripod result. That usually is more chaotic and has a sharper zig-zag to it, rather than the smoother back and forth seen here.
So what ruined his photo?
An earthquake. Yes, seriously.
Ashby-Peckham took this shot in South Auckland, New Zealand, around 8:57 p.m. local time on Nov. 1, 2015. At 8:58, a magnitude 2.2 earthquake hit a couple of hundred kilometers to the southeast.
Now, skepticism is called for here (the Reddit thread, where I first saw this, has a lot of back and forth about it). Could it be a coincidence? Sure, it could. My strongest doubt was that a quake that weak could be felt that far away. However, in an email discussion about it, Ashby-Peckham told me that another earthquake about the same distance away was indeed felt in Auckland. I’ve been in a couple of earthquakes that size when I lived in northern California, and they were enough to make my closet doors rattle.
From much farther away, it’s not out of the question that one that size could cause a small jiggle in a tripod. Remember, a tripod isn’t perfectly rigid, and it has the weight of the camera all the way on one end. Ask any photographer: A good breeze can cause the tripod to shake (though not likely in this case; the shaking started after the exposure began, lasted less than a second, and then nothing for the rest of the shot).
Usually, it’s maddening. In this case, it was literally Earth-shaking.
So this is a new one on me. Using the ISS as a virtual seismograph! It’s a pretty funny idea. I suppose if you live in a place with enough earthquakes you could actually calibrate your photography equipment to them, measuring how much the image wiggles versus size/distance of the quake. You need a moving target; stars don’t move quickly enough, and all you get is smeared-out disks for them (note that in the shot, the stars do appear to wiggle a bit). Of course, you could put the camera on a motor, letting it slowly scan the sky over and over again.
That seems like a lot of work, but maybe fun work. Or you could, y’know, just get a seismograph. Or just check the USGS quake page. That might work, too.
Tip o’ the lens cap to Peter Caltner.