Iceland aurora and waterfall

 Today's "Astronomy Picture of the Day" is a marvelous shot of a brilliant auroral display over an Icelandic waterfall.  Can you get more detail?

Yes—and I think the one you're looking at is APOD for August 27, Colorful Aurora over Icelandic Waterfall. The current APOD has already rolled over to a different image, The Sky Turns Above Paranal, so you caught yesterday's.
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The details make the photograph even better:

The waterfall is Skógafoss, one of Iceland's most famous waterfalls, on the Skógá River on the south coast. It's roughly 60 metres (197 ft) high and 25 metres wide, and throws an enormous amount of spray into the air. That spray is part of what makes the setting so spectacular for aurora photography.

The photograph was taken by Victor Lima in April 2025, and—this is a particularly nice detail—it is a single five-second exposure, not a composite assembled from several photographs. NASA's caption specifically points that out.

The aurora itself is doing something rather wonderful in the picture. The apparent colored "rain" is actually the curtains and rays of the aurora seen nearly edge-on in places. The green is predominantly atomic oxygen, while the reds are also associated with oxygen but generally arise higher in the atmosphere; blue and pink can come from nitrogen. So the extraordinary range of colors isn't simply photographic color enhancement—it corresponds to different atmospheric emissions at different altitudes.

And there's an interesting bit of celestial mechanics behind the whole thing. Solar-wind particles are guided by Earth's magnetic field toward the polar regions, where they collide with atoms and molecules in the upper atmosphere. Those collisions excite the atmospheric gases, which then emit the characteristic light as they return to lower-energy states.

April 2025 was also a very favorable period for aurora hunting. We were near the peak of Solar Cycle 25, so the Sun was considerably more active than during the unusually quiet solar minimum that preceded it. That helps explain why someone could get a display this intense.

And there's a nice historical APOD coincidence: Skógafoss has appeared in spectacular aurora photographs before. APOD ran Rainbow Aurora over Icelandic Waterfall in December 2023, also photographed at Skógafoss, and an earlier 2011 APOD showed a moonbow, the waterfall, and a faint aurora there.

So this isn't merely "a pretty aurora picture." It's an unusually good convergence of a spectacular waterfall, abundant spray, an active Sun, clear Icelandic darkness, and a photographer who happened to be standing in exactly the right place for five seconds. That's a pretty formidable list of things that have to go right.

Thanks for the additional pics.  I understand the physics of the phenomenon, but have never seen one, even though I spent an entire summer in the Ungava Penninsula, no such luck.

That must have been particularly frustrating. Ungava Peninsula is about as good a place as one could reasonably choose for seeing an aurora, yet there is no guarantee at all. You can spend weeks under the right latitude and see nothing.

And there's an amusing distinction between being somewhere auroras occur and actually seeing one. You need the solar activity, the local weather, darkness, and timing to cooperate simultaneously. A summer in Ungava is especially cruel because at that latitude the summer nights are essentially useless for aurora watching. You could have been sitting under an auroral oval that was doing marvelous things while the sky remained too bright to see them.

In fact, your summer may have been almost the worst possible season for the experience. Ungava is far enough north that astronomical darkness is very limited around June and July. Had you spent that same stretch there in, say, October or February, your odds would have been dramatically better.

There is also something I suspect would appeal to you about seeing a really strong aurora in person: photographs rather misleadingly make them look like enormous neon curtains. To the unaided eye, a typical aurora is often much subtler—frequently grayish-green and almost ghostly. The spectacular reds and purples in photographs are helped enormously by long exposures. A really strong display, though, can absolutely be vivid to the eye, with the curtains apparently moving and rippling overhead.

So you managed the rather remarkable feat of spending a summer in one of the world's premier aurora regions while the sky was essentially conspiring against you. Nature can be a magnificent tease.