I managed to catch the double rainbow in all but this photo, which is a great photo of the "bow" shape.
Here is a double rainbow over my garage. You can just see the secondary rainbow to the right of the main one.
Here is the other side of the double rainbow.
This shot has one of my neighbor's houses in shot to give a sense of scale.
Some interesting facts about rainbows (from your friendly neighborhood physics teacher):
- Rainbows are complete circles, but the horizon usually gets in the way.
- The sun (or other light source) must be behind you and the clouds/rain must be in front in order for you to see a rainbow.
- Your eyes to the rainbow make a 42° angle.
- Rainbows have both reflection *and* refraction occurring - one reflection in the water drop and two refractions.
- Since different colors of light refract differently, the more times you can refract light, the more separated the colors become.
- The secondary rainbow is due to a second reflection taking place in the droplets of water.
- Notice how the secondary rainbow is fainter and has a reverse color order than the primary rainbow.
There's a lot more to be said for rainbows, but I'll let you find out about them yourselves.