Like Jupiter and Saturn, Neptune's atmosphere is made up of hydrogen and helium, although it contains a higher proportion of "ices" like water, ammonia and methane. However, like Uranus, its interior is mostly made of ices and rock. Uranus and Neptune are normally considered "ice giants" because of this. Methane in the outermost regions partly causes the planet's blue appearance, although an unknown component makes Neptune's color a deeper blue compared to Uranus.