The Aurora Explained, More or Less
Cleverly, just in time for Christmas, the Aurora Color Television Project here at the Geophysical Institute has released a new videotape explaining---and showing---the northern lights. I had a chance to preview the not-quite-done tape a few weeks ago, and thought it was delightful.
Hey, it's always fun watching friends perform on TV. There on the screen were people I knew well, explaining aspects of the aurora in clear, simple terms; there I sat, watching the electronically packaged explanations roll by, even though two of the experts on the tape---Tom Hallinan and Dan Osborne---have offices right off the same laboratory where I watched. I could have wandered into their offices and asked questions of the real people.
But this once, taking what I was given was more fun than asking. For one thing, the on-tape explanations are good ones, and they come with really impressive illustrations. The tape, called The Aurora Explained, is the successor to an earlier videotape produced by the institute. That first effort consisted simply of scenes of the northern lights in action, with musical background provided by excerpts from Gordon Wright's Symphony in Ursa Major. Local scuttlebutt has it that the scientists working with television imagery of auroras grew tired of being hassled for spare data sets by everyone from network news services to their cousins' brothers-in-law, so they put some of their data on a tape.
It's worth noting that the data sets in question are images of colorful, often fast-moving auroras, captured by incredibly sensitive television cameras. To use Osborne's analogy, a typical home camcorder or a broadcaster's studio TV camera has a sensitivity equivalent to an ASA rating of about ten thousand. That's near ten times the sensitivity to light of a common film-using camera, but it's many times less sensitive than the institute's auroral TV camera: it has an ASA equivalent of about two million.
Because the camera can catch the faintest shimmer of light in a dark sky, it's proven to be a powerful tool for studying auroras. The scientists love it. So does everyone who sees the northern lights displays it has captured, which is why the Aurora Color Television Project issued a tape in the first place. They've sold thousands of them over the years---and received hundreds of requests for another tape, one that would also explain what the viewers were watching. Finally, with help from professionals in the University of Alaska Fairbanks Department of Journalism and Broadcasting, the project people have put together images and explanations.
The combination is effective. Thanks to some improbable visual aids, such as a pinball machine and a "Welcome to Fairbanks" sign, the tape gave me a real feeling for things I had known about auroras but hadn't really understood---hadn't felt in my bones, so to speak. That may give away the true level of my science understanding; according to Neal Brown, another scientist on the team and on the tape, the project aimed for an audience with about an eighth-grade education, "but nothing boring for a Ph.D. and nothing way beyond a third-grader."
With those limits, and with only a half-hour to show and tell what is known about auroras, the tape does leave room for more questions and answers. (Possibly with that in mind, the University of Alaska Press is selling a package of The Aurora Explained videotape along with a copy of The Aurora Watcher's Handbook---a set that together should answer enough questions to make anyone feel like an expert on auroras.) And, of course, watching auroras on videotape is not as overwhelming an experience as watching a grand display dance overhead. But then, on the tape auroras come with explanations, background music by Fairbanks composer Yonni Fischer, graphics by Deb Coccia and Dixon Jones---and they can be watched in the warmth of a living room.
Information on purchasing the aforementioned items can be found at the Aurora Color Television Project purchase information page.
