A Horizontal Rainbow Makes For Easier Trips to Oz

We've all seen our share of quadruple rainbows and rainbows from space, but it's not to often you catch on lying down one the job. A particularly lazy refraction showed up in Paris the other day, but it's not quite as it seems.

The rainbow is actually normal, but thanks to the angle of reflection (a high sun plus distant rain) this particular 'bow appears to be striping the horizon instead of arching into the sky because the bulk of it is hidden below the curve of the Earth. And for a mere, run-of-the-mill single rainbow, that's a pretty cool trick. [NASA]

Image by Bertrand Kulik