Which planets are called the gas giants?
The four outer planetsJupiter, Saturn, Uranus, and Neptuneare called the gas giant planets. Much larger than the rocky planets, they all have rings and many moons. They are made up mostly of hydrogen, helium, frozen water, ammonia, methane, and carbon monoxide. Jupiter and Saturn contain the largest percentages of hydrogen and helium, while Uranus and Neptune contain the largest amounts of ices (frozen water, ammonia, methane, and carbon dioxide).