The Clouds of Jupiter . ... Credit Copyright: Voyager Project , JPL , NASA Explanation: What makes the colors in Jupiter's clouds ? With a mean temperature of 120 degrees Kelvin (-153 degrees Celsius) and a composition dominated by hydrogen (about 90%), and helium (about 10%) with a smattering of hydrogen compounds like methane and ammonia, the blue, orange, and brown cloud bands and the salmon colored "red" spot are hard to explain. ... NASA Web Site Statements, Warnings, and Disclaimers . ...