Here’s a double sundog I caught in mist a few feet away one morning in Yosemite National Park: http://travel.nationalgeographic.com/travel/national-parks/yosemite-photos/#/yosemite-sunrise_2087_600x450.jpg

The key to that one may have been below-freezing temperatures, creating suspended ice crystals much like you’d get way up in the atmosphere with a typical sundog.

So it sounds like Phil saw the bottom half of the rainbow as he was looking down with the Sun high and behind him.

Oh, but my camera was in checked baggage!

Rob

Thank you very much for linking to the sundog.clara.co.uk site — both the pictures and the explanations are fantastic!

It’s often difficult to guess these things from just a description, but I’m thinking you were able to spot a “Sundog”. See if this link looks anything like what you saw: http://www.stormchaser.ca/Atmospheric_Optics/Halos_etc/Jan_Sundog_34.html

They don’t always show a multicolor spectrum in the glare, but the ones that do are very striking. I was lucky enough to see one (actually two, one on each side) a few months ago. It was quite brilliant and kept it’s luminosity for a good 20 minutes.

They are caused by falling ice-crystalls instead of raindrops like a rainbow. http://www.sundog.clara.co.uk/halo/parhelia.htm

There’s a waterfall not too far from here too, and it’s not rare to see rainbows in the droplets too. No matter really where you are relative to the sun, you can see them.

I’ll be at the AAS meeting in DC in January!

Ooh! Ooh! Ooh!
If I bring my copy of your book, will you autograph it?

Sorry I missed you at Tucson, by the way; I saw on your blog you were there. But I’ll be at the AAS meeting in DC in January!

Cartman: Eh. I hate those things.
Kyle: Nobody hates rainbows.
Stan: Yeah. What’s there to hate about rainbows?
Cartman: Well, you know. You’ll just be sitting there, minding your own business, and they’ll come marching in, and crawl up your leg, and start biting the inside of your , and you’ll be all like, “Hey! Get out of my you stupid rainbows!”
Stan: Cartman, what the are you talking about?
Cartman: I’m talking about rainbows. I hate those friggin’ things!
Kyle: Rainbows are those little arches of color that show up after a rainstorm.
Cartman: Oh. RainBOWS. Yeah, I like those. Those are cool.
Stan: What were you talking about?
Cartman: Huh? Oh nothing. Forget it.
Kyle: No. What marches in, crawls up your leg—
Cartman: Nothing.
Kyle: —and starts biting the inside of your ?
Cartman: Nothing!

Jeez! Everything’s an alien conspiracy these days. I suppose spirolina is actually a mind control organism planted here by aliens too! Wait, spirolina? I knew it! Are you serious? I hadn’t heard that one. Wait until they hear about this at the UFO convention!

But I’ve never been able to find any information about what conditions can create that phenomenon. Got any pointers?

http://www.seinfeldscripts.com/TheApology.htm

1) It’s part of a double rainbow. The light is being reflected from lower drops back into higher ones at the proper angle.

2) You can probably assume that the drops that have fallen as far as your waist are spherical, at least for purposes of back-of-the-envelope calculations. But this may be a very bad assumption for drops that have just left the shower head. The drops that have just broken off from the main jet probably still have some weird shape as momentum, surface tension, gravity, and air resistance interact. Some of these may be bending light in just the right way to send a colored flash into your eye.

It might be instructive to take a long exposure photo like your second one, to get a statistical sampling of the colors, and see whether they form a pattern.

(Shower physics: experiment with the one you love.)

I think the droplets flashing has something to do with the properties of the surface of the shower curtain. Does it reflect much light? What colour is it? Hmmm, you should take more showers in the afternoon

Seriously though, neato. Not much I can say about the red drops, so it must be aliens, or ghosts. Alien ghosts. Ever see Final Fantasy Spirits Within? Yeah, those things.

In the house where I grew up, the bathrooms were well inside the building, which is good because it meant we had a place to hide during tornado season. When I had an apartment in Cambridge, Mass., the shower had a little window set in the wall, which the sun would strike in early afternoon. If you took a shower from around 13:00 to 15:00, you’d get a rainbow. One more perk of being night-shifted was getting up at noon, eating a breakfast of ice cream and experiencing a shower full of spectra. (And of course, doing physics at midnight just feels so much more hard core.)