Jupiter's gossamer and main rings are red, whereas the inner halo ring is bluish. Scientists determine the color of the rings of Jupiter by examining the wavelengths of the particles making up the rings, and the way light scatters from them.
The rings are formed out of material from some of Jupiter's moons. The innermost ring, called the halo ring, differs in color from the other two sets of rings due to its unique shape, created by its closeness to Jupiter's powerful electromagnetic field. The differing shape changes the ring's spectral properties, making it blue even though it is composed of the same materials as the other ring sets.