Right after I retired in February, shot from my back deck. Aptos, CA
Nice, @squeegee . And I used to live up the road from you, off of Soquel - San Jose Road, near Summit. You live in a nice area.
Gorgeous rainbows. I used to get calendars with rainbow photos on them, and then use them for the lecture on rainbows I used to give my optics classes.
Several of these shots show double rainbows, which is cool. The colors in the secondary rainbow are reversed from those in the primary, and it’s weaker. The sky between the primary and secondary rainbow has less scattered light, so it can be dramatically darker, as seen in several of the above shots (especially AHunter3’s). This phenomenon was first recorded by Alexander of Aphrodisias. It’s called “Alexander’s Dark Band” in consequence. (Write your own joke about Alexander’s Rag Time Band here).
Sometimes you only get a portion of the rainbow – it depends where the raindrops are. Dung_Beetle’s shot shows an extreme case. And if you see a rainbow in early morning or late afternoon, when the sun is near the horizon, you can see a red rainbow, as eburacum45 correctly notes.
When Il lived in Utah, conditions were almost perfect for rainbows – you had the Wasatch mountains to the East of the valley where clouds would drop their rain, and in the evening you’d get a low sun giving you a high rainbow, sometimes red.
None of these pictures seem to clearly show supernumerary rainbows, which are a series of extra bands alternating pinkish and greenish inside the primary rainbow, within the violet band. They typically show up with larger raindrops of relatively uniform size, and when sunlight is particularly bright. I think you can see a little of them in the OP’s image and in AHunter3’s shot.
The number and distribution of colors changes with the size of raindrops, by the way. M. Minnaert has a table in his book The Nature of Light and Color in the Open Air (a great popular book on weird atmospheric optical phenomena) that tells you the size of the raindrops from the appearance of the rainbow. This page explains it. If the drops get small enough, there is no color separation at all, and you have a White Rainbow.
Interesting. Here is a picture from the web, from Popular Science.
A White Rainbow with supernumeraries! (those are the pink and green inner bands)
I’ve never seen a picture of that before. The other white rainbows I’ve seen in pictures were just the single bow. I’ve never seen one in real life.
The reason there’s no color separation, by the way, is because the diffraction caused by passing the light through what’s essentially a small aperture (the tiny drop) causes the band to widen out so much that the bands of all colors overlap, essentially undoing the prismatic separation, so the bow is still there, but it’s all white. The effect occurs when the drops are in sizes so small they approach the size of the optical wavelengths.
The western slope of Colorado. Grand junction. Idw but rainbows seem common there.
My avatar is my cat sitting in a prism rainbow. She kept to the purple and moved with it across the floor as the afternoon progressed.
If it weren’t for all those pesky trees in the way in that photo, you’d be looking down on Freedom blvd, directly at Aptos HS.
Soquel - San Jose Road is a pretty area, I drive that way pretty regularly to avoid highway 17. I have a friend who lives off Olive Springs up that way.
Very cool! Thanks for the info. I did not know that such a thing as white rainbows even existed until now.
Me neither! Thanks Cal!