Neptune is the eighth planet from the Sun and has a nice bright blue colour. Its bluer than Uranus, which has more green, because of an atmosphere that is composed of methane, hydrogen and helium. The high amount of methane absorbs just the red light from the visible spectrum and reflects the blue light. Hence Neptune appears very blue to us. The above picture of Neptune was taken by NASA’s Voyager space probe and focuses in on the planet’s dark spot (a very large anti-cyclonic storm system).