We recently had a fairly long discussion about the color spectrum, light, and pigments about a month ago. I was thinking about that today as I was driving my car.

As I was driving my car home today I passed an intersection with flashing yellow lights. It was dusk, and as I approached these flashing yellow lights, I looked right at them. To my surprise, for a split second they looked red. I was surprised by this, and decided to look again at the next set of flashing yellow lights. Again: for a split second they looked red as I approached them in my car and looked directly at them. (I was going approximately 80 miles per hour on a highway).

Can anyone provide an explanation for this? All light travels at the same speed, and so I see know reason why the light with red wavelength would reach my eyes at a noticeably sooner time than any of the other wavelengths. Is there any kind of optical illusion going on here?