Here’s a fascinating video by NASA that explains what auroras are and what they look like from space. It’s filled with beautiful photographs and time-lapse sequences captured by astronauts on the International Space Station. Astronaut photographer Don Pettit, who maintains a blog about his experiences, writes that taking pictures of Earth is harder than it looks:
Even with a shutter speed of 1/1000th of a second, eight meters (26 feet) of motion occurs during the exposure. Our 400-millimeter telephoto lens has a resolution of less than three meters on the ground. Simply pointing at a target and squeezing the shutter always yields a less-than-perfect image, and precise manual tracking must be done to capture truly sharp pictures. It usually takes a new space station crewmember a month of on-orbit practice to use the full capability of this telephoto lens.
Another surprisingly difficult aspect of Earth photography is capturing a specific target. If I want to take a picture of Silverton, Oregon, my hometown, I have about 10 to 15 seconds of prime nadir (the point directly below us) viewing time to take the picture. If the image is taken off the nadir, a distorted, squashed projection is obtained. If I float up to the window and see my target, it’s too late to take a picture. If the camera has the wrong lens, the memory card is full, the battery depleted, or the camera is on some non-standard setting enabled by its myriad buttons and knobs, the opportunity will be over by the time the situation is corrected. And some targets like my hometown, sitting in the middle of farmland, are low-contrast and difficult to find. If more than a few seconds are needed to spot the target, again the moment is lost. All of us have missed the chance to take that “good one.” Fortunately, when in orbit, what goes around comes around, and in a few days there will be another chance.
Time-lapse photographer Randy Halverson (whose time-lapse of lightning storms we featured last year) is back again with another epic time-lapse film. This one is packed with shots of some of the most beautiful things you can point your camera at in the night sky: the Milky Way, auroras, and shooting stars. It’s composed of thousands of 15-30 second exposures captured with a Canon 5D Mark II and Canon 60D at ISO 1600-6400, f/2.8, and 3 second intervals. Keep your eyes peeled at 53 seconds: you get to see a shooting star with a Persistent Train, which is the ionized gas left behind as the meteor burns up in our atmosphere!
One amazing perk that comes with being a NASA astronaut is that you can watch meteor showers up close and from above. Astronaut Ron Garan captured this awesome photograph from the International Space Station of a Perseid meteor burning up in our atmosphere.
By the way, did you notice the hot pixels littering the frame? That’s probably why NASA sometimes only uses DSLRs once before too many pixels are destroyed by space radiation.
Last week we featured a stunning time-lapse video that unfortunately failed to capture Perseid meteor shower well because of too much air traffic in the area. Landscape photographer Henry Jun Wah Lee attempted the same kind of video in Joshua Tree National Park. Even though there’s still quite a bit of air traffic, you can clearly see quite a few shooting stars that light up the sky.
Regarding the issue of shooting stars being so brief in a time-lapse video (an issue that arose in the comments of our previous post), Lee writes in the Vimeo comments:
Each of the meteors only last 1 frame but with so many during the meteor shower, it looks like a lot going on. Wide aperture also makes the trails look wider/more visible. And I angle the lens so that it picks up as much of the trail as possible when a meteor goes across the sky. In this case, I pointed away from the source direction. So you see longer streaks. I only use 1 second intervals between exposures for smooth motion.
The photos were shot with a Canon 5D Mark II and EF 16-35mm L lens at f/2.8, ISO6400, and 20 second exposures. There’s also the obligatory Sigur Ros music accompanying the video.