Supernumerary Bows

Bright rainbow with supernumeraries Several supernumerary arcs

When there is a bright rainbow it is worth looking out for additional bows inside the primary. These supernumerary bows are caused by interference and are more common toward the top of the bow.

When conditions are just right there may be several bows inside each other. In this close up two supernumeraries are visible.

Garden spray supernumerary bows Secondary supernumerary arcs

Supernumerary bows are easy to create with a garden spray, partly because of the smaller drop size but also because the sizes are more even. The brightening inside the primary and outside the secondary is very obvious here.

Apart from producing stronger bows inside the primary the spraybow can occasionally produce a supernumerary outside the secondary. This is very rare in a natural rainbow. Here this shows up as the faint orange band along the left edge of the secondary.

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