Iridescent colours arise in a different manner than most of the colours we see. Flowers, paints, clothing, and cat fur show colours from selective absorption. Some wavelengths (colours) are absorbed while others are reflected. The colours formed by iridescence arise from wave interference. Some wavelengths undergo mutual cancelation while others become reinforced.
When iridescence is seen, it usually appears on a fairly small scale: beetle wings, butterfly wings, hummingbird gorgets, duck feathers. But, when it comes to iridescence in the sky, it can be grand indeed. The nicest iridescence is usually seen in wave clouds near the Sun. I saw some today.
Iridescence in a wave cloud was seen today from the parking lot of the Nelson & District Community Complex.
Hi Alistair,
This is very unusual and something that I have never seen or even been aware of. Very much beyond beautiful I find it difficult to find a word or words to describe it. Thank you so much for sharing.
Sincerely,
Bill
I have seen that twice in the past year, over Kootenay Lake. I thought I was losing my mind it was so beautiful! I had never, in 71 years, seen that before. I wish I had seen this one.
The kaleidoscopic patterns and colours seen in iridescent wave clouds are a delight. Yet, it is interesting that we do not often see really nice displays. There are, perhaps, two reasons for this. First, wave clouds are most frequent just prior to winter storms, but that is also the time valley stratus obscures the view of them from where we live. Secondly, forming close to the Sun, the colours can be blindingly bright and so people avoid looking in their direction.
wow, that’s stunning a piece of art, could be felt art. thanks
I saw one on the Paulson ski trails a couple of weeks ago, but it was nothing compared to this. It looked wonderful with sunglasses on, but I could not get a decent photograph of it. This one is magnificent!
That’s exquisite. I do see what I call rainbow off-cuts fairly often, but not this magnificent. I can’t grasp it;
some wave lengths are reinforced, others mutually cancel,;is this determined by the molecular structure of the thing that is essentially different from that of the common little colors that grab or discard?
Pamella, similar examples of wave reinforcement and cancelation happen whenever there are waves, even water waves. Imagine waves, say, wakes of boats, from two similar sources having the same wavelength, but offset by half a wavelength. Then the crest of one happens to lie in the trough of the other, the two of them cancel to give nothing. But, if the crest overlies another crest, they reinforce to give twice the amplitude. This is true with light waves also. Locally some wavelengths will be enhanced and others diminished so we preferentially see one colour or another. Except with iridescence in clouds, the two sources are both sunlight, but sunlight that interacts with itself after passing around opposite sides of cloud droplets. Noise cancellation earphones rely on producing a sound that matches the noise but whose position (phase) is such that it cancels the original sound. So, one sound cancels another sound.
Ah, now I’m catching on. That’s fascinating. Thanks for the lucid explanation.