They are caused by certain chemicals in the clouds. There is still some uncertainty about this, but phosphorus is probably one of them.
Also there may be sulfur and various compounds of hydrogen.
I've just checked with a NASA page and they still aren't sure what causes the colors. It's one of those question where "don't know" is the right answer!
The horizontal stripes seen on Jupiter and Saturn are actually bands of clouds in their atmospheres. These bands are caused by different wind speeds and directions at different latitudes. The different cloud compositions and altitudes create variations in color and appearance along these bands.
Planet Jupiter.
Jupiter is the planet with prominent stripes, known as belts and zones, caused by its fast rotation and unique atmospheric dynamics.
Jupiter's white strips are formed by the tops of cloud formations in the planet's atmosphere which are formed by convection in the atmosphere modified by the coriolis force produced by the planet's rapid spin.
Horizontal stripes on Jupiter and Saturn are caused by fast-moving jet streams in their atmospheres. These bands of clouds are created by the planet's rapid rotation and heat distribution mechanisms, leading to alternating belts of lighter and darker cloud formations.
One of the planets with a band is Jupiter. Not only is Jupiter massive, but has multiple and striking stripes throughout.
belts.
Saturn & Jupiter.
The horizontal stripes seen on Jupiter and Saturn are actually bands of clouds in their atmospheres. These bands are caused by different wind speeds and directions at different latitudes. The different cloud compositions and altitudes create variations in color and appearance along these bands.
Jupiter has. (Also Saturn has, but not so obvious as Jupiter).
His stripes are orange and black.
Red and white are the colour of the stripes
Planet Jupiter.
Jupiter is the planet with prominent stripes, known as belts and zones, caused by its fast rotation and unique atmospheric dynamics.
Jupiter's white strips are formed by the tops of cloud formations in the planet's atmosphere which are formed by convection in the atmosphere modified by the coriolis force produced by the planet's rapid spin.
The stripes will be dark grey, almost black.
The stripes on the flag of the United States are red and white.